UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
Form 6-K
REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO
RULE 13a-16 OR
15d-16 UNDER THE SECURITIES EXCHANGE ACT OF 1934
For the month of March 2024
Commission File Number 001-35297
Fortuna Silver Mines Inc.
(Translation of registrant’s name into English)
200 Burrard Street, Suite 650, Vancouver,
British Columbia, Canada V6C 3L6
(Address of principal executive office)
Indicate by check mark whether the registrant files or will file annual
reports under cover of Form 20-F or Form 40-F.
Indicate by check mark if the registrant is submitting the Form 6-K
in paper as permitted by Regulation S-T Rule 101(b)(1):
¨
Indicate by check
mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T
Rule 101(b)(7): ¨
SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.
|
Fortuna Silver
Mines Inc. |
|
(Registrant) |
|
|
Date: March 8, 2024 |
By: |
/s/
"Jorge Ganoza Durant" |
|
|
Jorge Ganoza Durant |
|
|
President and CEO |
Exhibits:
Exhibit 99.1
Fortuna Silver Mines
Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report
Effective Date:
December 31, 2023
Prepared by |
Eric Chapman |
|
Senior Vice President of Technical
Services - Fortuna Silver Mines Inc. |
|
|
|
Paul Weedon |
|
Senior Vice President of Exploration
- Fortuna Silver Mines Inc. |
|
|
|
Raul Espinoza |
|
Director of Technical Services
- Fortuna Silver Mines Inc. |
|
|
|
Mathieu Veillette |
|
Director, Geotechnical, Tailings
and Water - Fortuna Silver Mines Inc. |
|
|
|
Patricia Gonzalez |
|
Director of Operations - Compania
Minera Cuzcatlan S.A. de C.V. |
Suite 650, 200 Burrard Street,
Vancouver, BC, V6C 3L6 Tel: (604) 484 4085, Fax: (604) 484 4029
|
|
Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Contents
|
1.1 |
Introduction |
15 |
|
1.2 |
Property description, location and access |
15 |
|
1.3 |
Mineral tenure, surface rights and royalties |
15 |
|
1.4 |
History |
16 |
|
1.5 |
Geology and mineralization |
16 |
|
1.6 |
Drilling and sampling |
16 |
|
1.7 |
Data verification |
19 |
|
1.8 |
Mineral processing and metallurgical testing |
19 |
|
1.9 |
Mineral Resources |
20 |
|
1.10 |
Mineral Reserves |
21 |
|
1.11 |
Mining methods |
23 |
|
1.12 |
Recovery methods |
23 |
|
1.13 |
Project infrastructure |
24 |
|
1.14 |
Market studies and contracts |
24 |
|
1.15 |
Environmental studies and permitting |
25 |
|
1.16 |
Capital and operating costs |
26 |
|
1.17 |
Economic analysis |
26 |
|
1.18 |
Conclusions |
27 |
|
1.19 |
Risks and opportunities |
27 |
|
1.20 |
Recommendations |
28 |
|
|
1.20.1 Exploration activities |
28 |
|
|
1.20.2 Technical and operational studies |
29 |
|
2.1 |
Report purpose |
30 |
|
2.2 |
Qualified persons |
30 |
|
2.3 |
Scope of personal inspection |
30 |
|
2.4 |
Effective dates |
31 |
|
2.5 |
Previous technical reports |
31 |
|
2.6 |
Information sources and references |
32 |
3 |
Reliance on Other Experts |
34 |
4 |
Property Description and Location |
35 |
|
4.1 |
Mineral tenure |
36 |
|
|
4.1.1 Mining claims and concessions |
36 |
|
4.2 |
Surface rights |
37 |
|
4.3 |
Royalties |
39 |
December 31, 2023 | Page 2 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
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|
4.3.1 |
Mexico Mining Tax |
39 |
|
4.4 |
Environmental aspects |
40 |
|
|
4.4.1 |
Term extension of EA 1731-2009 |
40 |
|
|
4.4.2 |
Mine closure |
40 |
|
|
4.4.3 |
Other risks or liabilities |
41 |
|
4.5 |
Permits |
41 |
|
4.6 |
Comment on Section 4 |
41 |
5 |
Accessibility, Climate, Local
Resources, Infrastructure and Physiography |
42 |
|
5.1 |
Access |
42 |
|
5.2 |
Climate |
42 |
|
5.3 |
Topography, elevation and vegetation |
42 |
|
5.4 |
Infrastructure |
42 |
|
5.5 |
Sufficiency of surface rights |
43 |
|
5.6 |
Comment on Section 5 |
43 |
|
6.1 |
Ownership history |
44 |
|
6.2 |
Exploration history |
44 |
|
6.3 |
Production history |
45 |
|
|
6.3.1 |
Cuzcatlan |
45 |
7 |
Geological Setting and Mineralization |
45 |
|
7.1 |
Regional geology |
46 |
|
7.2 |
Local geology |
47 |
|
7.3 |
Project geology |
48 |
|
|
7.3.1 |
Stratigraphy |
49 |
|
|
7.3.2 |
Structural geology |
50 |
|
7.4 |
Description of mineralized zones |
51 |
|
|
7.4.1 |
Trinidad deposit |
52 |
|
|
7.4.2 |
Victoria mineralized zone |
55 |
|
7.5 |
Comment on Section 7 |
57 |
|
8.1 |
Mineral deposit type |
67 |
|
8.2 |
Exploration model |
68 |
|
8.3 |
Comment on Section 8 |
69 |
|
9.1 |
Exploration conducted by Pan American
Silver |
70 |
|
9.2 |
Exploration conducted by Continuum |
70 |
|
9.3 |
Exploration conducted by Cuzcatlan |
70 |
December 31, 2023 | Page 3 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
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|
9.3.1 |
Geophysics |
70 |
|
|
9.3.2 |
Fluid inclusion and petrographic studies |
71 |
|
|
9.3.3 |
Terraspec analysis |
71 |
|
|
9.3.4 |
Geological mapping |
71 |
|
|
9.3.5 |
ASTER study |
74 |
|
9.4 |
Exploration potential |
74 |
|
9.5 |
Comment on Section 9 |
76 |
|
10.1 |
Introduction |
77 |
|
10.2 |
Drilling Campaigns |
79 |
|
|
10.2.1 |
Pan American campaign (2001) |
79 |
|
|
10.2.2 |
Continuum campaigns (2004 to 2006) |
80 |
|
|
10.2.3 |
Cuzcatlan campaigns (2006 to 2023) |
80 |
|
10.3 |
Drilling conducted post database cut-off
date |
82 |
|
10.4 |
Geological and geotechnical logging procedures |
84 |
|
10.5 |
Drill core recovery |
85 |
|
10.6 |
Extent of drilling |
85 |
|
10.7 |
Drill hole collar surveys |
86 |
|
10.8 |
Downhole surveys |
86 |
|
10.9 |
Drill sections |
86 |
|
10.10 |
Sample length versus true thickness |
91 |
|
10.11 |
Summary of drill intercepts |
91 |
|
10.12 |
Comment on Section 10 |
92 |
11 |
Sample Preparation, Analyses,
and Security |
93 |
|
11.1 |
Sample preparation prior to dispatch of
samples |
93 |
|
|
11.1.1 |
Channel chip sampling |
93 |
|
|
11.1.2 |
Core sampling |
94 |
|
|
11.1.3 |
Bulk density determination |
94 |
|
11.2 |
Dispatch of samples, sample preparation,
assaying and analytical procedures |
94 |
|
|
11.2.1 |
Sample dispatch |
94 |
|
|
11.2.2 |
Sample preparation |
95 |
|
|
11.2.3 |
Sample analysis |
96 |
|
11.3 |
Laboratory accreditation |
97 |
|
11.4 |
Sample security and chain of custody |
98 |
|
11.5 |
Quality control measures |
99 |
|
|
11.5.1 |
Certified reference material |
99 |
|
|
11.5.2 |
Blanks |
101 |
|
|
11.5.3 |
Duplicates |
101 |
|
|
11.5.4 |
Conclusions regarding quality control results |
104 |
December 31, 2023 | Page 4 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
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11.6 |
Comment on Section 11 |
104 |
|
12.1 |
Introduction |
105 |
|
|
12.1.1 |
Pan American and Continuum |
105 |
|
|
12.1.2 |
Cuzcatlan |
105 |
|
12.2 |
Database |
105 |
|
12.3 |
Collars and downhole surveys |
106 |
|
12.4 |
Geological logs and assays |
106 |
|
12.5 |
Geotechnical and hydrogeology |
107 |
|
12.6 |
Metallurgical recoveries |
107 |
|
12.7 |
Mineral Resource estimation |
108 |
|
12.8 |
Mineral Reserve estimation |
108 |
|
12.9 |
Mine reconciliation |
109 |
|
12.10 |
Site visits |
109 |
|
12.11 |
Comment on Section 12 |
109 |
13 |
Mineral Processing and Metallurgical
Testing |
110 |
|
13.1 |
Metallurgical tests |
111 |
|
|
13.1.1 |
Whole rock analysis |
111 |
|
|
13.1.2 |
Bond ball mill work index |
111 |
|
|
13.1.3 |
Locked cycle flotation |
112 |
|
|
13.1.4 |
Thickening and Filtering |
113 |
|
13.2 |
Deleterious elements |
113 |
|
13.3 |
Comment on Section 13 |
113 |
14 |
Mineral Resource Estimates |
114 |
|
14.1 |
Introduction |
114 |
|
14.2 |
Disclosure |
114 |
|
|
14.2.1 |
Known issues that materially affect
Mineral Resources |
114 |
|
14.3 |
Assumptions, methods and parameters |
115 |
|
14.4 |
Supplied data, data transformations and
data validation |
115 |
|
|
14.4.1 |
Data transformations |
115 |
|
|
14.4.2 |
Software |
115 |
|
|
14.4.3 |
Data preparation |
116 |
|
|
14.4.4 |
Data validation |
116 |
|
14.5 |
Geological interpretation and domaining |
116 |
|
14.6 |
Exploratory data analysis |
118 |
|
|
14.6.1 |
Compositing of assay intervals |
118 |
|
|
14.6.2 |
Statistical analysis of composites |
119 |
|
|
14.6.3 |
Sub-domaining |
120 |
December 31, 2023 | Page 5 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
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|
14.6.4 |
Extreme value treatment |
120 |
|
|
14.6.5 |
Boundary conditions |
123 |
|
|
14.6.6 |
Sample type comparison |
123 |
|
|
14.6.7 |
Grade correlation |
123 |
|
|
14.6.8 |
Continuity analysis |
124 |
|
|
14.6.9 |
Variogram modeling |
124 |
|
|
14.6.10 |
Opinion on the quality of the modeled variograms |
126 |
|
|
14.6.11 |
Selective mining unit |
126 |
|
14.7 |
Grade interpolation |
127 |
|
14.8 |
Bulk density |
127 |
|
14.9 |
Estimation validation |
128 |
|
|
14.9.1 |
Global validation |
128 |
|
|
14.9.2 |
Local validation |
129 |
|
|
14.9.3 |
Visual validation |
130 |
|
|
14.9.4 |
Mine reconciliation |
130 |
|
|
14.10 |
Mineral Resource depletion |
131 |
|
14.11 |
Mineral Resource classification |
131 |
|
|
14.11.1 |
Geological continuity |
131 |
|
|
14.11.2 |
Data density and orientation |
131 |
|
|
14.11.3 |
Data accuracy and precision |
132 |
|
|
14.11.4 |
Spatial grade continuity |
132 |
|
|
14.11.5 |
Classification |
133 |
|
14.12 |
Mineral Resource reporting |
134 |
|
|
14.12.1 |
Reasonable prospects for eventual economic extraction |
134 |
|
|
14.12.2 |
Mineral Resource statement |
134 |
|
|
14.12.3 |
Mineral Resources by key geologic attributes |
135 |
|
|
14.12.4 |
Comparison to previous estimates |
137 |
|
14.13 |
Sequential Gaussian Simulation |
137 |
|
14.14 |
Comment on Section 14 |
139 |
15 |
Mineral Reserve Estimates |
140 |
|
15.1 |
Mineral Resources handover |
140 |
|
15.2 |
Mineral Reserve methodology |
140 |
|
15.3 |
Key Mining Parameters |
141 |
|
|
15.3.1 |
Mining Recovery |
141 |
|
|
15.3.2 |
Dilution |
141 |
|
|
15.3.3 |
Metal prices, metallurgical recovery, and NSR values |
142 |
|
15.4 |
Cut-off grade determination |
143 |
|
15.5 |
Mineral Reserves |
144 |
|
15.6 |
Comment on Section 15 |
145 |
December 31, 2023 | Page 6 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
|
16.1 |
Introduction |
146 |
|
16.2 |
Hydrogeology |
146 |
|
16.3 |
Mine geotechnical |
146 |
|
16.4 |
Mining method |
147 |
|
16.5 |
Mine production schedule |
150 |
|
|
16.5.1 |
Mineable stope optimization |
150 |
|
16.6 |
Underground mine model |
152 |
|
|
16.6.1 |
Mine layout |
152 |
|
|
16.6.2 |
Lateral development |
152 |
|
|
16.6.3 |
Raising requirements |
153 |
|
16.7 |
Equipment, manpower, services, and infrastructure |
153 |
|
|
16.7.1 |
Contractor development |
153 |
|
|
16.7.2 |
Mining equipment |
153 |
|
|
16.7.3 |
Mine manpower |
153 |
|
|
16.7.4 |
Underground drilling |
153 |
|
|
16.7.5 |
Ore and waste handling |
154 |
|
|
16.7.6 |
Mine ventilation |
154 |
|
|
16.7.7 |
Backfill method |
155 |
|
|
16.7.8 |
Mine dewatering system |
155 |
|
|
16.7.9 |
Maintenance facilities |
156 |
|
|
16.7.10 |
Power distribution |
156 |
|
|
16.7.11 |
Other services and infrastructure |
159 |
|
16.8 |
Comment on Section 16 |
159 |
|
17.1 |
Crushing and milling circuits |
160 |
|
|
17.1.1 |
Crushing |
160 |
|
|
17.1.2 |
Milling and classification |
160 |
|
|
17.1.3 |
Flotation |
160 |
|
|
17.1.4 |
Thickening, filtering, and shipping |
161 |
|
17.2 |
Requirements for energy, water, and process
materials |
163 |
|
17.3 |
Comment on Section 17 |
163 |
18 |
Project Infrastructure |
164 |
|
18.1 |
Introduction |
164 |
|
18.2 |
Roads |
164 |
|
18.3 |
Tailing disposal facilities |
164 |
|
|
18.3.1 |
Tailings dam |
166 |
|
|
18.3.2 |
Dry stack |
166 |
|
18.4 |
Mine waste stockpiles |
167 |
December 31, 2023 | Page 7 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
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18.5 |
Ore stockpiles |
167 |
|
18.6 |
Concentrate transportation |
167 |
|
18.7 |
Power generation |
167 |
|
|
18.7.1 |
Principal substation |
168 |
|
|
18.7.2 |
Distribution |
168 |
|
|
18.7.3 |
Mine distribution |
168 |
|
18.8 |
Communications systems |
169 |
|
18.9 |
Comment on Section 18 |
170 |
19 |
Market Studies and Contracts |
171 |
|
19.1 |
Market studies |
171 |
|
19.2 |
Commodity price projections |
171 |
|
19.3 |
Contracts |
171 |
|
|
19.3.1 |
Silver–gold concentrate |
171 |
|
|
19.3.2 |
Operations |
171 |
|
19.4 |
Comment on Section 19 |
172 |
20 |
Environmental Studies, Permitting
and Social or Community Impact |
173 |
|
20.1 |
Introduction |
173 |
|
20.2 |
Regulation and permitting |
173 |
|
|
20.2.1 |
Environmental legislation |
173 |
|
|
20.2.2 |
Environmental obligations |
173 |
|
|
20.2.3 |
Other obligations |
173 |
|
|
20.2.4 |
Permitting |
173 |
|
20.3 |
Environmental baseline |
174 |
|
|
20.3.1 |
Climate |
174 |
|
|
20.3.2 |
Air quality |
175 |
|
|
20.3.3 |
Water quality |
175 |
|
|
20.3.4 |
Hydrology |
175 |
|
|
20.3.5 |
Soil |
175 |
|
|
20.3.6 |
Fauna and flora |
175 |
|
|
20.3.7 |
Ecosystem characterization |
175 |
|
|
20.3.8 |
Protected areas and archaeology |
176 |
|
|
20.3.9 |
Environmental risks and management plan |
176 |
|
|
20.3.10 |
Environmental areas of focus |
176 |
|
|
20.3.11 |
Operations and management |
176 |
|
20.4 |
Community relations |
177 |
|
|
20.4.1 |
Socioeconomic and cultural aspects |
177 |
|
|
20.4.2 |
Stakeholder engagement |
178 |
|
|
20.4.3 |
Community development |
178 |
|
20.5 |
Mine closure |
180 |
December 31, 2023 | Page 8 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
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20.5.1 |
Legal requirements and other obligations |
180 |
|
|
20.5.2 |
Mine closure management |
181 |
|
|
20.5.3 |
Reclamation and closure of affected areas |
183 |
|
|
20.5.4 |
Monitoring during closure |
183 |
|
|
20.5.5 |
Monitoring post closure |
184 |
|
|
20.5.6 |
Closure costs |
184 |
|
20.6 |
Greenhouse gas (GHG) emissions |
184 |
|
20.7 |
Comment on Section 20 |
184 |
21 |
Capital and Operating Costs |
185 |
|
21.1 |
Sustaining capital costs |
185 |
|
21.2 |
Operating costs |
185 |
|
21.3 |
Comment on Section 21 |
186 |
|
22.1 |
Economic analysis |
187 |
|
22.2 |
Comments on Section 22 |
187 |
23 |
Adjacent Properties |
188 |
24 |
Other Relevant Data and Information |
189 |
25 |
Interpretation and Conclusions |
190 |
|
25.1 |
Mineral tenure, surface rights, water rights,
royalties and agreements |
190 |
|
25.2 |
Geology and mineralization |
190 |
|
25.3 |
Exploration, drilling and analytical data
collection in support of Mineral Resource estimation |
191 |
|
|
25.3.1 |
Data verification |
191 |
|
25.4 |
Metallurgical testwork |
192 |
|
25.5 |
Mineral Resource estimation |
193 |
|
25.6 |
Mineral Reserve estimation |
194 |
|
25.7 |
Mine plan |
195 |
|
25.8 |
Recovery |
195 |
|
25.9 |
Infrastructure |
195 |
|
25.10 |
Markets and contracts |
196 |
|
25.11 |
Environmental, permitting and social considerations |
196 |
|
25.12 |
Capital and operating costs |
197 |
|
25.13 |
Economic analysis |
197 |
|
25.14 |
Risks and opportunities |
197 |
|
26.1 |
Introduction |
199 |
|
26.2 |
Exploration |
199 |
December 31, 2023 | Page 9 of 208 |
| |
|
|
26.2.1 |
Trinidad deposit |
199 |
|
|
26.2.2 |
Victoria mineralized zone |
199 |
|
|
26.2.3 |
Taviche corridor |
199 |
|
|
26.2.4 |
Maria vein |
199 |
|
|
26.2.5 |
Other |
199 |
|
26.3 |
Technical and Operational |
200 |
|
|
26.3.1 |
Mineral Resources and Reserves |
200 |
|
|
26.3.2 |
Mining and Processing |
200 |
December 31, 2023 | Page 10 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
|
Table 1.1 Mineral Resources as of
December 31, 2023 |
21 |
|
Table 1.2 Mineral Reserves as of December 31,
2023 |
22 |
|
Table 1.3 Summary of projected operating costs in 2024 |
26 |
|
Table 2.1 Acronyms |
33 |
|
Table 4.1 Mineral concessions owned by Cuzcatlan |
36 |
|
Table 4.2 Usufruct contracts registered by Cuzcatlan
for land usage at San Jose |
38 |
|
Table 6.1 Production figures during Cuzcatlan management
of the San Jose Mine |
45 |
|
Table 8.1 Trinidad deposit and Victoria mineralized
zone characteristics |
68 |
|
Table 10.1 Drilling by company and period at the San
Jose Mine |
77 |
|
Table 10.2 Drilling by core diameter size |
79 |
|
Table 10.3 Drill intervals in the Trinidad deposit
and Victoria mineralized zone encountered post data cut-off date |
82 |
|
Table 10.4 Example of typical drill results at the
Trinidad Deposit and Victoria mineralized zone |
91 |
|
Table 11.1 Duplicate types used by Cuzcatlan |
101 |
|
Table 13.1 Plant concentrate and recovery values since
2012 |
112 |
|
Table 14.1 Data used in the 2023 Mineral Resource update
of the Trinidad deposit and Victoria mineralized zone |
116 |
|
Table 14.2 Univariate statistics of undeclustered drill
hole and channel composites by vein |
119 |
|
Table 14.3 Top cut thresholds by vein |
121 |
|
Table 14.4 Correlation coefficients of gold and silver
grades by vein |
123 |
|
Table 14.5 Variogram model normal score parameters |
125 |
|
Table 14.6 Block model parameters |
126 |
|
Table 14.7 Density statistics by vein |
127 |
|
Table 14.8 Global estimation validation |
128 |
|
Table 14.9 Mineral Resources exclusive of Mineral Reserves
reported as of December 31, 2023 |
135 |
|
Table 14.10 Mineral Resources inclusive of Mineral
Reserves reported as of December 31, 2023 |
136 |
|
Table 14.11 Mineral Resources inclusive of Mineral
Reserves by vein reported as of December 31, 2023 |
136 |
|
Table 15.1 Parameters used for NSR determination |
143 |
|
Table 15.2 Operating cost by area and mining method |
143 |
|
Table 15.3 Mineral Reserves as of December 31,
2023 |
144 |
|
Table 16.1 Geomechanical classification used at the
San Jose Mine |
147 |
|
Table 16.2 San Jose Mine life-of-mine production plan
2024 |
150 |
December 31, 2023 | Page 11 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
|
Table 16.3 Lateral development for
the San Jose in 2024 |
152 |
|
Table 16.4 Vertical development for the San Jose in
2024 |
153 |
|
Table 16.5 Mine air flow requirements |
154 |
|
Table 16.6 Air flow in-out balance |
155 |
|
Table 16.7 Transformer capacities |
157 |
|
Table 17.1 Reagent consumption of the San Jose processing
plant |
163 |
|
Table 18.1 Volumes and life of the dry stack tailings
facility |
167 |
|
Table 20.1 Main stakeholder groups at the San Jose
Mine |
178 |
|
Table 21.1 Summary of projected operating costs in
2024 |
185 |
December 31, 2023 | Page 12 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
|
Figure 4.1 Map showing the location
of the San Jose Mine |
35 |
|
Figure 4.2 Location of mining concessions at the San
Jose Property |
37 |
|
Figure 7.1 Map of Oaxaca state showing approximate
distribution of Cenozoic volcanic rocks and underlying tectonostratigraphic terranes |
46 |
|
Figure 7.2 Local geology of the San Jose Mine area |
47 |
|
Figure 7.3 Geology of the San Jose Mine area |
48 |
|
Figure 7.4 Stratigraphic column of the San Jose Mine
area |
49 |
|
Figure 7.5 Trinidad and Victoria alteration assemblages
and zonation |
53 |
|
Figure 7.6 Plan map showing location of resource drilling
and orientation of sections |
58 |
|
Figure 7.7 Section displaying lithology along
1846925N |
59 |
|
Figure 7.8 Section displaying lithology along
1846975N |
60 |
|
Figure 7.9 Section displaying lithology along
1847500N |
61 |
|
Figure 7.10 Section displaying lithology along
1848200N |
62 |
|
Figure 7.11 Longitudinal section of Trinidad vein displaying
Ag Eq isogrades |
63 |
|
Figure 7.12 Longitudinal section of Bonanza vein displaying
Ag Eq isogrades |
64 |
|
Figure 7.13 Longitudinal section of Stockwork mineralization
Zones displaying Ag Eq isogrades |
65 |
|
Figure 7.14 Longitudinal section of Victoria main structure
displaying Ag Eq isogrades |
66 |
|
Figure 8.1 Classification of epithermal and base metal
deposits |
67 |
|
Figure 8.2 Exploration model: extension-related pull-apart
basins |
69 |
|
Figure 9.1 Map showing location of exploration programs
conducted by Cuzcatlan at the San Jose Mine |
72 |
|
Figure 9.2 Map showing location of generative exploration
programs |
75 |
|
Figure 10.1 Drill hole location map for the San Jose
Mine |
78 |
|
Figure 10.2 Graph of core recovery of Trinidad Deposit
and Victoria mineralized zone |
85 |
|
Figure 10.3 Section displaying mineralization
along 1846925N |
87 |
|
Figure 10.4 Section displaying mineralization
along 1846975N |
88 |
|
Figure 10.5 Section displaying mineralization
along 1847500N |
89 |
|
Figure 10.6 Section displaying mineralization
along 1848200N |
90 |
|
Figure 14.1 3D perspective of Trinidad and Victoria
deposits showing vein wireframes |
117 |
|
Figure 14.2 Length of samples assayed |
118 |
|
Figure 14.3 Swath plot for gold grades in the Stockwork
vein |
129 |
|
Figure 14.4 Visual validation of estimated block grades
versus composites – Stockwork vein |
130 |
|
Figure 14.5 Long section of Stockwork
vein displaying Mineral Resource categorization criteria |
134 |
December 31, 2023 | Page 13 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
|
Figure 15.1 Idealized diagram demonstrating
the methodology for determining operating dilution |
142 |
|
Figure 16.1 Mechanized mining sequence |
148 |
|
Figure 16.2 Optimized mineable areas for the San Jose
Mine |
151 |
|
Figure 16.3 Mine layout |
152 |
|
Figure 17.1 Crushing and milling circuits at the San
Jose processing plant |
162 |
|
Figure 18.1 Plan view of mine and processing plant
area |
164 |
|
Figure 18.2 Location map of tailings storage facilities |
165 |
|
Figure 18.3 Schematic drawing showing phase 1, phase
2 and phase 3 tailings dam |
166 |
December 31, 2023 | Page 14 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Fortuna Silver Mines Inc. (Fortuna) has
compiled a Technical Report (the Report) on the San Jose Mine (the San Jose Project or the Project) located in Oaxaca, Mexico
The mineral rights of the San Jose Mine
are held by Compania Minera Cuzcatlan S.A. de C.V. (Cuzcatlan). Cuzcatlan is a Mexican subsidiary that is 100 % indirectly owned by Fortuna
and is responsible for running the underground silver-gold mine.
The Report discloses updated Mineral
Resource and Mineral Reserve estimates for the Project.
Costs are in US dollars (US$) unless
otherwise indicated.
| 1.2 | Property
description, location and access |
The mine is located in the central portion
of the state of Oaxaca, Mexico.
The San Jose Mine area is characterized
by gently sloping hills and adjoining colluvial-covered plains. Elevations above mean sea level range from approximately 1,540 m to 1,675 m.
The vegetation is grasslands and thornbush that are typical of dry savannah climates being temperate in nature with an average annual
temperature of 19.5ºC. Mining operations are conducted on a year-round basis.
The mine
site is 47 km by road south of the city of Oaxaca, which provides access to an international airport, and 0.8 km east of federal highway
175, the major highway between Oaxaca and Puerto Angel on the Pacific coast. The village of San Jose del Progreso is located 2
km to the southeast of the mine site.
| 1.3 | Mineral
tenure, surface rights and royalties |
The Project consists of mineral rights
for 22 mining concessions all located in the state of Oaxaca for a total surface area of approximately 47,844 hectares (ha). Tenure is
held in the name of Cuzcatlan with all mining concessions having an expiry date beyond the expected mine life.
Cuzcatlan has signed 45 usufruct contracts,
which have been registered before the National Agrarian Registry, with landowners to cover the surface area needed for the operation
and tailings facilities.
The San Jose Mine is not subject to any
back-in rights, liens, payments or encumbrances.
There are royalties attached to the mineral
concessions, however, the only royalties that affect the Mineral Reserves and have been considered in the economic analysis are:
| · | A
1.5 % royalty to Maverix on the Reduccion Taviche Oeste concession. |
| · | A
3 % royalty on the Progreso concession and a 1 % royalty the Reduccion Taviche Oeste concession
payable to SGM. |
December 31, 2023 | Page 15 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
The Project has a long history of small
mining operations, dating from the 1850s.
Companies
with involvement in the Project prior to Fortuna’s interest include Pan American Silver, Minerales de Oaxaca S.A., and Continuum
Resources Ltd. (Continuum). Work completed included surface and underground mapping, chip-channel sampling of the surface and underground
workings, core drilling, and mining activities.
In November 2005, Fortuna reached
an agreement with Continuum to earn a 70 % interest in Continuum’s interests. Fortuna acquired a 100 % interest in the Project
in 2009.
Work completed
by Fortuna and Cuzcatlan since 2009 has included geological mapping, a remote-sensing-based geological study, airborne geophysical surveys
(airborne magnetometric and gamma-ray spectrometry), fluid inclusion and petrographic studies, core and RC drilling, metallurgical
testwork, mining studies, environmental baseline and supporting studies, social outreach, and underground mining activities.
Total production from the mine from September 2011
through December 31, 2023, is estimated as 66.8 Moz of silver and 457 koz of gold.
| 1.5 | Geology
and mineralization |
The silver-gold deposit at the San Jose
Mine is a typical low-sulfidation epithermal deposit.
The San Jose Mine area is underlain by
a thick sequence of sub-horizontal andesitic to dacitic volcanic and volcaniclastic rocks of presumed Paleogene age. These units have
been significantly displaced along major north and northwest-trending extensional fault systems with the precious metal mineralization
being hosted in hydrothermal breccias, crackle breccias, and sheeted stockwork-like zones of quartz/carbonate veins emplaced within zones
of high paleo permeability associated with the extensional structures.
The mineralized structural corridor extends
for more than 3 km in a north-south direction and has been subdivided into the Trinidad deposit, San Ignacio and Victoria areas. The
Mineral Resource and Mineral Reserve estimates discussed in this Report are located in the Trinidad deposit and Victoria areas.
The major mineralized structure in the
Trinidad deposit area consists of a sheeted and stockwork quartz–carbonate vein system referred to as the main Stockwork Zone located
between the primary Trinidad and Bonanza structures. In addition, several secondary vein systems are present locally in the hanging wall
and footwall of the Trinidad and Bonanza structures.
The Victoria mineralized zone is located
approximately 350 m east of the Trinidad vein and north of the current underground operations of the San Jose Mine. It is structurally
related to the same extensional behavior that dominates the Trinidad deposit with a similar style of mineralization, corresponding to
a low sulfidation epithermal deposit formed in a shallow crustal environment with a relatively low temperature resulting in the precipitation
of silver and gold mineralization.
As of June 30, 2023, the data cut-off
date for estimation of Mineral Resources, a total of 1,460 drill holes totaling 463,774.55 m have been completed at the San Jose Mine,
with the
December 31, 2023 | Page 16 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
drilling being concentrated in the Trinidad deposit area and extensions to the south of the mineralized structural system.
Wide-spaced exploration drilling has
also been completed in the San Ignacio area along the southern extension of the structurally controlled mineralized corridor and to the
far north of the Trinidad deposit, as well as in the Victoria mineralized zone, Los Diaz, Maria and Taviche projects. All of the drilling
was conducted using core drilling methods with the exception of 1,476 m of reverse circulation (RC) pre-collars in six of the 1,460 diamond
drill holes.
A total of 1,110 core holes totaling
330,951.55 m have been drilled in the Trinidad deposit area and 205 holes totaling 75,229.25 m in the Victoria mineralized zone. In Trinidad,
the majority of the holes have been drilled from east to west to crosscut the steeply east-dipping mineralized zone at high angles, whereas
in the Victoria mineralized zone, the holes have been drilled from west to east from underground to intersect the subvertical Victoria
main structure. Of the 1,315 holes, 320 have been drilled from the surface and the remainder from underground.
The core drilling typically commences
with HQ-(63.5 mm diameter) core and continues to the maximum depth allowable based on the mechanical capabilities of the drill equipment.
Once this point is reached or poor ground conditions are encountered the hole is cased and further drilling undertaken with smaller diameter
drilling tools with the core diameter being reduced to NQ2 (50.6 mm) or NQ-size (47.6 mm) to completion of the hole. In the Trinidad
deposit, five of the drill holes were further reduced to BQ-size (36.5 mm) diameter to complete the drill holes to the target depths.
All the drilling completed in the project area has been carried out by contract drilling service companies. Ground conditions are generally
good with core recovery averaging 99 %.
Surface drill hole collars were surveyed
using differential global positioning system (GPS) and total station survey methods. Concrete monuments are constructed at each collar
location recording the drill hole name, azimuth, inclination and total depth. At locations where the drill hole collar is located in
a cultivated field, the collar monument is constructed approximately 50 cm below the actual surface.
Underground drill hole collars were surveyed
using total station survey methods. Concrete monuments similar to those used for surface collars are constructed to mark the location
with the drill hole name, azimuth, inclination and total depth recorded.
Down-hole surveys have been completed
for 1,443 of the 1,460 drill holes completed as of the data cut-off date. For the 17 holes where downhole surveys are not recorded, all
of which were drilled prior to 2007 with only three being drilled in the Trinidad deposit. The azimuth and dip orientation of these holes
was recorded at the collar to account for drilling direction. The absence of downhole surveys in three of the 1,315 holes drilled at
Trinidad and Victoria is not regarded as material to the Mineral Resource estimate.
Downhole surveys are typically completed
at 50 m intervals although recent drill holes include downhole surveys at 10 m intervals until reaching 50 m depth and then at 50 m intervals
thereafter. All downhole surveys have been carried out by the drilling contractor using Reflex electronic downhole survey tools.
As of the effective date of this Report,
drilling has been conducted at the Trinidad deposit over a strike length of approximately 2,500 m and to depths exceeding 1,000 m from
surface. Exploration drilling has generally increased in depth to the north. Drilling of the Victoria mineralized zone has been conducted
over a strike length of approximately 1,700
December 31, 2023 | Page 17 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
m and covers a vertical extent of approximately 550 m, with upper holes intersecting the
structure approximately 250 m below the surface.
The relationship between the sample intercept
lengths and the true width of the mineralization varies in relation to the intersect angle between the steeply dipping zone of mineralized
veins and the inclined nature of the diamond core holes. Calculated estimated true widths are always reported together with actual sample
lengths by taking into account the angle of intersection between drill hole and the mineralized structure.
In 2018, all logging became digital,
being incorporated daily into the Maxwell Datashed database system. Data were initially recorded using Excel templates, and later with
the Maxwell LogChief application using essentially the same structure. Both input methods used picklists and data validation rules to
ensure consistency between loggers. Separate pages were designed to capture metadata, lithology, alteration, minerals (sulfides,
oxides, and limonite), structure (contacts, fractures, veins, and faults with attitudes to core axis). Intensity of alteration phases
was recorded using a numeric 1 to 4 scale (weak, moderate, strong, complete).
Geotechnical logging consists of the
collection of specified data fields including recovery percentage and rock quality designation (RQD) length. Joint filling and joint
weathering were described. A tablet-based data entry program was developed by Cuzcatlan using the Maxwell LogChief software. Data checks
are implemented into this program to prevent entry of erroneous data.
The sampling methodology, preparation,
and analyses differ depending on whether it is drill core or a channel sample. All samples are collected by Cuzcatlan geological staff
with sample preparation and analysis being conducted either at the onsite Cuzcatlan Laboratory or transported to the ALS Global preparation
facility in Guadalajara prior to being sent on for analysis at their laboratory in Vancouver.
The Cuzcatlan Laboratory used since 2012
for assaying channel samples was accredited as a testing laboratory with the requirements of ISO/IEC 17025:2005 for sample preparation
and assaying of silver and gold on March 2, 2018. Prior to this date, the laboratory was not certified. The Cuzcatlan Laboratory
is not independent of Fortuna/Cuzcatlan.
The ALS Global Laboratory is an independent,
privately-owned analytical laboratory group. The Vancouver laboratory holds ISO 17025 accreditation. The Mexican laboratory holds ISO
9001:2000 certification.
The SGS Laboratory used by Cuzcatlan
as an umpire laboratory is an independent privately-owned analytical laboratory located in Durango, Mexico and holds ISO/IEC 17025:2005
accreditation for sample preparation and assaying.
Channel chip samples are generally collected
from the face of newly exposed underground workings. The entire process is carried out under the mine geology department’s supervision.
Sampling is carried out at 3 m intervals within the drifts and stopes of all veins. The channel’s length and orientation are identified
using paint in the underground working and by painting the channel number on the footwall. The channel is typically approximately 20
cm wide and approximately 1 to 2 cm deep, with each individual sample preferably being no smaller than 0.4 m and no longer than 1.5 m.
Drill core is laid out for sampling and
logging at the core logging facility at the camp. Sample intervals are marked on the core and depths recorded on the appropriate box.
A geologist is responsible for determining and marking the drill core intervals to be sampled, selecting
December 31, 2023 | Page 18 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
them based on geological and
structural logging. The sample length must not exceed 2 m or be less than 20 cm.
All samples collected by Cuzcatlan are
assayed by atomic absorption (AA) spectroscopy and by fire assay (FA) with gravimetric finish. For drill samples only, a full suite of
trace elements is analyzed using an aqua regia digestion followed by inductively-coupled plasma (ICP) analysis. Assay results and certificates
are reported electronically by e-mail. Since mid-2018, the onsite laboratory has also assayed channel samples and selected composites
for fluorine using a selective ion electrode technique.
Bulk density samples have been primarily
sourced from drill core with a limited number being sampled from underground workings. Bulk density measurements are performed at the
ALS Global Laboratory in Vancouver using an industry-standard wax coated water immersion technique.
Sample collection and transportation
of drill core and channel samples is the responsibility of and the Cuzcatlan mine geology and brownfields exploration departments and
must follow strict security and chain of custody requirements established by Fortuna. Samples are retained in accordance with the Fortuna
corporate quality assurance/quality control (QAQC) procedures.
Fortuna implemented a full QAQC program
to monitor the sampling, sample preparation and analytical process for all drilling campaigns in accordance with its companywide procedures.
The program involved the routine insertion of certified reference materials, blanks, and duplicates. Evaluation of the QAQC data indicates
that the data are sufficiently accurate and precise to support Mineral Resource estimation.
Data verification programs performed
by the QPs on the data collected by Cuzcatlan are adequate to support Mineral Resource and Mineral Reserve estimation.
| 1.8 | Mineral
processing and metallurgical testing |
Initial metallurgical test work was completed
in support of pre-feasibility studies with Cuzcatlan continuing to build on this original work with additional tests to support operational
requirements.
Work completed included whole rock analysis, Bond
ball mill work index, grind calibration. rougher flotation test work with three stages of cleaning, locked cycle flotation test work
and rougher kinetics flotation. Data was used to design the process plant, which has been in operation for 12 years, since 2011.
It is the opinion of the QP that the
San Jose Mine has an extensive body of metallurgical investigation comprising several phases of testwork as well as an extensive history
of treating ore at the operation since 2011. In the opinion of the QP, the San Jose metallurgical samples tested and the ore that is
presently treated in the plant is representative of the material included in the life-of-mine plan (LOMP) in respect to grade and metallurgical
response. In 2022, the geology department provided 25 samples from the Victoria mineralized zone for testing. The metallurgical recoveries
obtained for silver head grades in the range of 120-160 g/t were 87.7-90.1% for gold (Au) and 88.1-89.7% for silver (Ag). Therefore,
the samples exhibit a metallurgical recovery trend similar to the current operation within that range of Ag head grades. Additionally,
mineralogy did not detect any mineral types different from those currently being processed at the Trinidad deposit.
December 31, 2023 | Page 19 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Metallurgical recovery is estimated to
be constant for the LOMP at 90.54 % for silver and 89.82 % for gold. Differences between vein systems are minimal with regard to recovery.
There is no indication that the characteristics
of the material planned for mining will change and therefore the recovery assumptions applied for future mining are considered as reasonable
for the LOMP.
Deleterious elements detected in ore
in specific parts of the deposit have the potential to affect economics due to potential smelting penalties, including elevated levels
of fluorine (>1,000 ppm). These levels have been considered in the financial analysis.
Iron-oxide minerals (hematite) have been
identified in ore processed from mineralization associated with the highest levels of the mine. Elevated iron-oxide has been found to
lower metallurgical recovery in the plant by approximately 5 %. Testwork is ongoing to optimize the plant to maximize recovery from this
material that will potentially be processed in batches so as not to impact the recovery of sulfide ore.
Mineral Resource estimation involved
the usage of drill hole and channel samples in conjunction with underground mapping to construct three-dimensional wireframes to define
individual vein structures. Samples were selected inside these wireframes, coded, composited and top cuts applied if applicable. Boundaries
were treated as hard with statistical and geostatistical analysis conducted on composites identified in individual veins. Silver and
gold grades were estimated into a geological block model consisting of 4 m x 4 m x 4 m selective mining units (SMUs) representing
each vein. All veins were estimated by ordinary kriging (OK) with risk analysis conducted by sequential Gaussian simulation. Estimated
grades were validated globally, locally, visually, and (where possible) through production reconciliation prior to tabulation of Mineral
Resources.
Resource confidence classification considers
a number of aspects affecting confidence in the resource estimation including: geological continuity and complexity; data density and
orientation; data accuracy and precision; grade continuity; and simulated grade variability. Mineral Resources were classified as Measured, Indicated
and Inferred on a combination of the distance to the nearest sample, kriging efficiencies, and the slope of regression.
Mineral Resources are reported based
on underground mining within mineable stope shapes based on actual operational costs and mining equipment sizes using silver equivalent
grades in the block model calculated based on the projected long term metal prices and actual metallurgical recoveries experienced in
the plant using the following formula:
Ag Eq (g/t) = Ag (g/t)
+ (Au (g/t)*((1,880/23.90)*(91/90)).
Mineral Resources are reported above
a cut-off grade of 130 g/t Ag Eq based on operating costs of US$ 84.94/t comprised of US$ 38.31/t for mining, US$ 20.79/t for plant,
and US$ 25.92 for all other costs including general services and administration, distribution, community and social relations.
By
the application of a silver equivalent value taking into consideration the average metallurgical recovery and long-term metal prices
for each metal, and the determination of a reasonable cut-off grade using actual operating costs, as well as the exclusion of Mineral
Resources identified as being isolated or economically unviable using a floating stope optimizer, the Mineral Resources have ‘reasonable
prospects for eventual economic extraction’.
December 31, 2023 | Page 20 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Mineral Resources exclusive of Mineral
Reserves as of December 31, 2023, are reported in Table 1.1. Mineral Resources that are not Mineral Reserves do not have demonstrated
economic viability. Mineral Resources are reported insitu, using the 2014 CIM Definition Standards. Eric Chapman P. Geo, a Fortuna employee,
is the Qualified Person for the estimate.
Table 1.1 Mineral Resources as of
December 31, 2023
Classification |
Tonnes (000) |
Ag (g/t) |
Au (g/t) |
Contained Metal |
Ag (Moz) |
Au (koz) |
Measured |
45 |
141 |
1.09 |
0.2 |
2 |
Indicated |
1,001 |
148 |
1.11 |
4.7 |
36 |
Measured + Indicated |
1,046 |
147 |
1.11 |
5.0 |
37 |
Inferred |
1,029 |
147 |
1.04 |
4.9 |
35 |
Notes:
| · | Mineral
Resources are reported insitu, using the 2014 CIM Definition Standards for Mineral Resources
and Mineral Reserves. |
| · | Mineral
Resources are exclusive of Mineral Reserves. Mineral Resources that are not Mineral Reserves,
do not have demonstrated economic viability. |
| · | Mineral
Resources are reported as of December 31, 2023. |
| · | Mr. Eric
Chapman, P. Geo., a Fortuna employee, is the Qualified Person for the estimate. |
| · | Mineral
Resources are reported based on underground mining within optimized stope designs using a
cut-off grade of 130 g/t Ag Eq based on assumed metal prices of US$ 23.90/oz Ag and
US$ 1,880/oz Au, estimated metallurgical recovery rates of 91 % for Ag and 90 % for
Au (Ag Eq (g/t) = Ag (g/t) + (Au (g/t)*((1,880/23.90)*(91/90)), and an average mining cost
of US$ 38.31/t, processing cost of US$ 20.79/t and other costs including general administrative &
services and distribution of US$ 25.92. |
| · | Mineral
Resource tonnes are rounded to the nearest thousand. |
| · | Totals
may not add due to rounding. |
Factors that may affect the estimates
include metal price and exchange rate assumptions; changes to the assumptions used to generate the cut-off grade; changes in local interpretations
of mineralization geometry and continuity of mineralized zones; changes to geological and mineralization shape and geological and grade
continuity assumptions; variations in density and domain assignments; geometallurgical assumptions; changes to geotechnical, mining,
dilution, and metallurgical recovery assumptions; changes to input and design parameter assumptions that pertain to the conceptual stope
designs constraining the estimates; and assumptions as to the continued ability to access the site, retain mineral and surface rights
titles, maintain environment and other regulatory permits, and maintain the social license to operate.
Mineral Reserves were converted from
Measured and Indicated Mineral Resources. Inferred Mineral Resources were set to waste.
Mineral
Reserves assume overhand cut and fill (OCF) or sublevel stoping (SLS) mining methods.
The overall mining recovery is approximately
92 % which takes into account the presence of pillars in wide veins and crown pillars for each main level of the mine.
Two sources
of dilution were considered, operational dilution and mucking dilution. Operational dilution for OCF averages 13.4 % if a zero
grade for the waste material is
December 31, 2023 | Page 21 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
applied. In the case of SLS, the operation dilution averages 16.7 %. Mucking dilution was estimated as
1 % and applied to both mining methods.
Metal prices used for Mineral Reserve
estimation were determined as of June 2023 by the corporate financial department of Fortuna based on market consensus.
Metallurgical recoveries were based on
metallurgical testwork and operational results at the plant from July 2022 to June 2023.
Net smelter return (NSR) values were
dependent on various parameters including metal prices, metallurgical recovery, price deductions, refining charges and penalties.
A breakeven cut-off grade was determined
based on all variable and fixed costs applicable to the operation. These include exploitation and treatment costs, general expenses and
administrative and commercialization costs (including concentrate transportation). The cut-off grade determination does not include costs
associated with management fees, community support activities, institutional relations, capital expenditures, SG&A expenses, Brownfields
exploration or closure costs., with the expectation that these costs will be covered by the operations cash flow or by Fortuna. The breakeven
cut-off grade was determined to be 150 g/t Ag Eq for OCF and 132 g/t Ag Eq for SLS. For the Reduccion Taviche Oeste concession where
an additional 2.5 % royalty is payable, the cutoff was 153 g/t Ag Eq cut-off for OCF and 135 g/t Ag Eq for SLS. For the Progreso mineral
concession where a 3% royalty may be payable, the break-even cut-off grade would be increased to 154 g/t Ag Eq in OCF and 136 g/t Ag Eq
in SLS.
SLS mining will be used for 82 % of the
total Mineral Reserves with OCF mining representing the remainder.
Mineral
Reserves as of December 31, 2023, are reported in Table 1.2. Mineral Reserves are reported at the point of delivery to the process
plant, using the 2014 CIM Definition Standards. The Qualified Person for the estimate is Mr. Raul Espinoza, FAusIMM (CP),
a Fortuna employee.
Table 1.2 Mineral Reserves as of December 31,
2023
Classification |
Tonnes (000) |
Ag (g/t) |
Au (g/t) |
Contained Metal |
Ag (Moz) |
Au (koz) |
Proven |
37 |
172 |
1.23 |
0.2 |
1.5 |
Probable |
695 |
155 |
0.97 |
3.5 |
21.7 |
Proven + Probable |
733 |
156 |
0.98 |
3.7 |
23.1 |
Notes:
| · | Mineral
Reserves are reported at the point of delivery to the process plant using the 2014 CIM Definition
Standards. |
| · | Mineral
Reserves are reported as of December 31, 2023. |
| · | Mr. Raul
Espinoza, FAusIMM (CP), a Fortuna employee, is the Qualified Person for the estimate. |
| · | Mineral
Reserves are reported based on underground mining within optimized stope designs using an
NSR breakeven cut-off for cut and fill mining methods of US$ 96.54/t, equivalent to 150 g/t
Ag Eq and an NSR breakeven cut-off for sublevel stoping mining methods of US$ 85.02/t, equivalent
to 132 g/t Ag Eq. An additional 2.5 % royalty is applied to the cut-off for Mineral Reserves
mined from the Reduccion Taviche Oeste concession and a 3.0 % royalty is applied to the cut-off
for Mineral Reserves mined from the Progreso concession. |
| · | Metal
prices used in the NSR evaluation are US$ 23.90/oz for silver and US$ 1,880/oz for gold. |
December 31, 2023 | Page 22 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
| · | Metallurgical
recovery values used in the NSR evaluation are 90.5 % for silver and 89.8 % for gold based
on actual plant recoveries. |
| · | NSR
values taking into account refining charges used in the estimation are US$ 20.08/oz for silver
and US$ 1,586.16/oz for gold with the exception of material located in the Reduccion Taviche
Oeste concession where NSR values are US$ 19.57/oz for silver and US$ 1,546.31/oz for gold
and Progreso concession where NSR values are US$ 19.47/oz for silver and US$ 1,538.34/oz
for gold. |
| · | Costs
used in NSR breakeven cut-off determination are US$ 49.83/t for cut and fill mining method;
US$ 38.31/t for sublevel stoping mining method; US$ 20.79/t for processing; and US$ 25.92/t
for other costs including distribution, general service and administration. |
| · | Mining
recovery is estimated to average 92 % and mining dilution is estimated at 17 %. |
| · | Mineral
Reserve tonnes are rounded to the nearest thousand. |
| · | Totals
may not add due to rounding. |
Mining uses conventional underground
methods, consisting of OCF and SLS.
Geotechnical recommendations used in
the mine design are based on a combination of rock mass rating and geotechnical strength index data.
Water inflows are currently managed using
five pumping stations installed at different levels of the mine. One future pumping station is planned for construction in 2024, in accordance
with the LOMP requirements.
Mineral Reserves are estimated at 0.7
million tonnes as of December 31, 2023, which is sufficient for a one-year LOMP consisting of 350 days at an average mill throughput
rate of 2,100 tonnes per day (tpd). Production in 2024 is estimated to be approximately 3.2 Moz of silver and 20 koz of gold based on
an average head grade of 156 g/t Ag and 0.98 g/t Au. Mine life will be complete by the end of 2024 unless additional Mineral Reserves
are discovered through exploration drilling or reduction in costs.
Access to the San Jose underground mine
is from surface through a main ramp. The San Jose Mine has been designed with a separation of 100 m between levels primarily to limit
blast vibration but also to assist with hanging wall and footwall stability.
Transportation of ore and waste is performed
via trucks with a 14 m3 and 7 m3 of capacity through the main and secondary ramps.
The ventilation requirements for the
mine to produce 2,100 tpd is 615,593 cfm. The ventilation system brings all the intake air through the main ramp and three main airway
networks. Exhaust air is forced to the surface from inside the mine by three principal fans, two operating at 250,000 cfm and one at
120,000 cfm.
The mine uses two kinds of backfill;
waste rock backfill generated during underground mining and paste fill.
The mobile equipment fleet is based on
the current mining operations, which is known to achieve the production targets set out in the LOMP.
Mine infrastructure and supporting facilities
are sufficient for the remaining LOMP.
The process design is based on metallurgical
testwork completed on samples from the deposit. The design and equipment are conventional.
December 31, 2023 | Page 23 of 208 |
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Technical Report |
The process plant design is split into
four principal stages including: crushing; milling; flotation; and thickening, filtering and shipping. The plant has a 3,000 tpd throughput
rate.
Energy requirements at the operation
are provided by a State power line of 115 kV which supplies two power transformers of 7 to 8 MVA capacity.
The plant requires 2.7 m3
of water to process one tonne of ore, of which 92 % comes from the recirculation process, and the remaining 8 % from the waste-water
treatment plant in Ocotlan.
The plant uses conventional reagents,
including a frother, collectors, flocculant and a depressor.
| 1.13 | Project
infrastructure |
The mine
has a relatively small surface footprint with the property boundary split into two parts, a north area covering the operational
footprint, and a south area covering the area of the tailings storage facility.
Infrastructure consists primarily of
the concentration plant, electrical power station, water storage facilities, filtered dry stack tailings facility, tailings dam, stockpiles,
and workshop facilities, all connected by unsealed roads.
Additional facilities include offices,
dining hall, laboratory, core logging and core storage warehouses.
All process buildings and offices for
operating the mine have been constructed, with camp facilities not required due to the proximity of the site to urban areas.
The tailings
facility is located approximately 1,500 m to the southwest of the concentration plant. The current dry stack tailings facility
has a total capacity to 4,033,000 m3, which is sufficient for the LOMP.
The mine currently has one waste stockpile
used for storing waste material that could not be effectively disposed of underground. There is sufficient remaining capacity for LOMP
requirements.
The mine currently has two ore stockpiles
which store low-grade silver ore, or material pending evaluation (due to mixing of different ore types).
Tractor trailers that can transport two
25 t containers each are used to transport concentrate by road to the port of Veracruz in the State of Veracruz for subsequent shipping
to purchasers in 400 to 600 t lots.
Power is
provided to the mine from the main grid via a 115,000-volt circuit, as well as a secondary reserve power supply line, all managed
by Federal Electricity Commission (CFE).
| 1.14 | Market
studies and contracts |
Since the operation commenced commercial
production in September 2011, a corporate decision was made to sell the concentrate on the open market. In order to get the best
commercial terms for the concentrates, it is Fortuna’s policy to sign contracts for periods no longer than one year. In 2023 Cuzcatlan
agreed a short-term contract to sell concentrate to Trafigura PTE LTD (15,000 t) and Arrow Metals (15,000 t) for 12 months.
December 31, 2023 | Page 24 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
All commercial terms entered between
the buyer and Cuzcatlan are regarded confidential but are considered to be within standard industry norms.
The QPs
have reviewed the key input information and consider that the data reflect a range of analyst predictions that are consistent with those
used by industry peers. Based on these sources, price projections are considered acceptable as consensus prices for use in mine
planning and financial analyses for the San Jose Mine in the context of this Report.
A price estimate of US$23.90/oz for silver
and US$1,880/oz for gold has been applied, based on mean consensus prices projected for 2024.
Cuzcatlan has used a Mexican peso exchange
rate of 19 pesos to the US dollar for financial analysis purposes, which conforms with general industry-consensus.
Cuzcatlan
has 14 major contracts for services relating to operations at the mine regarding: mining activities, ground support, raise boring, drilling,
transportation, electrical installations, plant and mine maintenance, explosives and civil works. The costs of such contracts are accounted
for in the capital and operating expenditure depending on work performed. Contracts are negotiated and renewed as needed. Contract
terms are typical of similar contracts in Mexico that Fortuna is familiar with.
The QP has reviewed the information provided
by Fortuna on marketing, contracts, metal price projections and exchange rate forecasts and notes that the information provided supports
the assumptions used in this Report and is consistent with the source documents, and that the information is consistent with what is
publicly available within industry norms.
| 1.15 | Environmental
studies and permitting |
Numerous baseline and supporting studies
were completed, covering areas including climate, air and water quality, hydrology, soil, flora, fauna, ecosystem characterization, identification
of protected areas and archaeology.
No significant environmental risks were
identified in the environmental baseline studies. During the operation stage, environmental risks and mitigation measures for the operation
stage are determined on an annual basis.
Cuzcatlan has an environmental management
and monitoring plan that includes follow-up on environmental programs for flora and fauna management, management of urban solid waste,
special waste, hazardous waste, and mining waste, as well as a surface and groundwater monitoring plans, environmental noise monitoring,
monitoring of the survival rate of flora included in reforestation programs, and a wildlife monitoring plan. Sustainability indicators
have also been defined and their performance monitored monthly.
The mining operation has been developed
in strict compliance with the Mexican regulations and permits required by the government agencies involved in the mining sector. In addition,
all work follows the international quality and safety standards set forth under standards ISO 14001 and OHSAS 18000.
To the extent known, all permits that
are required by Mexican law for the mining operation have been obtained. The tailings facility has sufficient storage capacity to support
the currently reported Mineral Reserves and LOMP.
Cuzcatlan continues developing sustainable
annual programs for the benefit of local communities, including educational, nutritional and economic programs. The social and environmental
responsibilities support a good relationship between the company and local
December 31, 2023 | Page 25 of 208 |
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Technical Report |
communities. This will aid the development and continuity
of the mining operation and improve the standard of living and economies of local communities.
The mine plan anticipates closure of
the operation in late 2024. The Company has assigned a dedicated team to review and update a multiyear progressive mine closure and monitoring
plan with a current estimated budget of US$ 27 million, which will begin its implementation during 2024. Multiple considerations are
being included such as closure-related technical studies and designs, remediation of affected areas, decommissioning and removal of infrastructure,
landform reshaping, revegetation, and value-added activities for the communities associated with progressive closure, repurposing, and
where appropriate, long-term monitoring and maintenance, whilst adhering to strict compliance with mine closure governmental regulations
and high international standards.
| 1.16 | Capital
and operating costs |
As the mine has entered its last planned
year of operation, sustaining capital expenses such as mine development meters, infill drilling, mine equipment and other necessary expenses
have been considered as part of operating costs and covered by the projected cash flow generation in 2024.
The projected operating costs are based
on the LOMP mining and processing requirements for 2024, as well as historical information regarding performance, operational and administrative
support demands.
Operating costs include site costs and
operating expenses to maintain the operation. These operating costs are analyzed on a functional basis and the cost structure is not
similar to the operating costs reported by the financial statements published by Fortuna Silver Mines Inc.
Site costs relate to activities performed
on the property including mine, plant, indirect and distribution of the commercial products. Community relations and capital expenditure
costs are projected to be covered by Cuzcatlan’s cash flows in 2024. Brownfields explorations costs and closure costs sustained
after mining activities have ceased are planned to be paid by Fortuna’s cash flow from its four other operating mines.
Projected
operating costs for the LOMP are detailed in Table 1.3.
Table 1.3 Summary of projected operating
costs in 2024
Area |
Units |
Q1 |
Q2 |
Q3 |
Q4 |
Total |
Mine |
US$/t |
60 |
56 |
43 |
39 |
48 |
Plant |
US$/t |
29 |
29 |
20 |
19 |
23 |
Indirect |
US$/t |
31 |
31 |
21 |
19 |
24 |
Distribution |
US$/t |
8 |
9 |
7 |
7 |
8 |
Community Relations |
US$/t |
5 |
6 |
4 |
3 |
4 |
Capital expenditure |
US$/t |
15 |
24 |
10 |
6 |
12 |
Total |
US$/t |
148 |
155 |
104 |
93 |
120 |
Fortuna is using the provision for producing
issuers, whereby producing issuers may exclude the information required under Item 22 for technical reports on properties currently in
production and where no material production expansion is planned.
December 31, 2023 | Page 26 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
The global after-tax financial results
exhibit a negative outcome when factoring in exploration costs and the total mine closure cost. However, the projected financial outcome
for 2024, considering only operational costs, shows a positive result. Fortuna expresses its commitment to covering Brownfields exploration
costs for 2024 and the subsequent expenses upon cessation of mining operations using funds derived from corporate profits. Given this,
the QP believes it is reasonable to continue mining operations throughout the planned operational period in 2024 to alleviate the negative
financial and social results of mine closure and support the current Mineral Reserve declaration under two assumptions:
| · | Fortuna
will cover the mines Brownfields exploration and closure costs at the corporate level. |
| · | Adequate
financial support is secured from Fortuna's other mining units, which, as per plans, will
be operational until 2035 and are expected to generate sufficient proceeds to cover closure
costs at San Jose. |
An economic analysis was performed in
support of the estimation of Mineral Reserves that, when costs associated with Brownfields exploration and closure were excluded, demonstrated
a positive cash flow that provides the QP reasonability to continue mining operations through the planned operational period in 2024
while a more detailed closure plan for the mine is prepared.
| 1.19 | Risks
and opportunities |
Opportunities include:
| · | Improvements
in mining productivity through optimizing the mining cycle. As shotcreting comprises a significant
component of the mining cycle, tests are being done to reduce the curing time from three
to two hours which would improve the mining cycle. |
| · | Completing
the raise bore initiatives currently underway in the central and northern zones of the Trinidad
deposit. This will ensure 100 % air coverage throughout the remainder of the mine life. |
| · | Definition
of Mineral Reserves associated with higher-grade mineralization identified in the Victoria
mineralized structure. |
| · | Exploration
potential exists for the Yessi vein, a new blind zone of alteration and brecciation that
has been interpreted as striking northwest to southeast and intersecting the Victoria mineralized
zone, where drilling has intercepted some high-grade gold and silver mineralization. |
Risks include:
| · | On
January 2, 2023, SEMARNAT served Cuzcatlan a resolution confirming the nullity of the previously granted 12-year EIA extension.
Cuzcatlan challenged the annulment of the EIA via a nullity trial presented before the Federal Administrative Court in Mexico City on
January 10, 2023. On October 30, 2023, the Mexican Federal Administrative Court ruled in favor of Cuzcatlan and re-instated
the 12-year EIA. The decision of the Mexican Federal Administrative Court has been appealed and was admitted by the Collegiate Court
in January 2024. |
December 31, 2023 | Page 27 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
| | Cuzcatlan
filed a response with the Collegiate Court in February 2024. A decision of the Collegiate
Court is expected within the next six to 12 months. The permanent injunction that Cuzcatlan
already has remains in effect. |
| | |
| · | Metallurgical
recovery could be lower than estimated in ore that is estimated to have an elevated iron
oxide content, which represents approximately 30 % of the plant feed in the LOMP. |
Recommendations for the next phase of
work have been broken into those related to ongoing exploration activities and those related to additional technical and operational
studies. Recommended work programs are independent of each other and can be conducted concurrently unless otherwise stated. The exploration-related
programs are estimated at a total cost of US$3.94 million. The operational improvement studies are recommended to be conducted in-house
and therefore do not involve a direct cost.
| 1.20.1 | Exploration
activities |
| · | Exploration
of the Trinidad deposit. It is recommended that Cuzcatlan continue to explore Trinidad
central sector and exploration of the behavior of the Trinidad system at depth to investigate
the potential for mineralization being hosted by the Mesoproterozoic basement. The program
would involve the drilling of 3,300 m of core at an estimated cost of US$ 450,000. |
| · | Exploration
of the Yessi vein. It is recommended that Cuzcatlan continue to explore Yessi vein discovered
in August 2023 to better define the geometry of the structures and establish the continuity
in mineralization. Recommended drilling includes 4,000 m of core at an estimated cost of
US$ 690,000. |
| · | Exploration
of the Taviche Corridor. An extensive and systematic field exploration program has been
carried out since 2020 including a drone magnetometric assessment, structural analysis, fluid
inclusion studies and detailed field work activities resulting in the definition of a first
stage drilling program proposal including 4,600 m in 17 core holes over six structures with
geological potential, including the San Juan, San Juan 2, Pastal, San Francisco, Consuelos
and San Nicolas areas; at an estimated cost of US$ 1,500,000.
The execution of this exploration program is dependent on obtaining the necessary permits
from the government and may not be executed if such permits are denied. |
| · | Exploration
of the Maria vein. This vein was first explored in 2017 with 3 holes, defining the
presence of a dilational region in the convergence of the Maria vein and the footwall of
the Trinidad vein. It is recommended that Cuzcatlan continue to explore the possible kinematic
indicators related to extension in the footwall of the Trinidad trend south of the current
operations with the drilling of 1,500 m of core at an estimated cost of US$ 290,000. |
| · | Other
exploration programs. The Guila prospect, located on the Reduccion Tlacolula 2 concession
of the San Jose mining property, has been identified as an area that has high potential for
the discovery of epithermal veins based on detailed surface mapping. It is recommended that
permits be obtained to allow targets to be drilled on this concession. If permits are obtained
a drill program consisting of 9,000 m of core holes at an estimated cost of US$ 1,400,000
is recommended. |
December 31, 2023 | Page 28 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
| 1.20.2 | Technical
and operational studies |
| · | Delineation
(infill) drilling. It is recommended that Cuzcatlan continue the delineation drilling
from underground of the Trinidad deposit and Victoria mineralized zone. A total of 20,600
m of core drilling is recommended at a budgeted cost of US$ 2,200,000. |
| · | Assess
the mining potential of the Victoria mineralized zone. A detailed evaluation is recommended
to determine the economic viability of accessing and mining the higher-grade zones of the
Victoria mineralized structure. This will be completed utilizing the operations resources
and part of normal operating cost. |
| · | Bulk
density measurements. It is recommended that the number of bulk density measurements
be increased in secondary veins. If sufficient measurements are obtained, bulk density can
be estimated rather than the presently used density assignment methodology. |
| · | Mining
method. As
part of the continuous improvement initiatives to reduce mining cost and to increase mine
productivity, it is recommended to continue with the mining evaluation and geomechanical
conditions for each stope, considering the possibility of increasing the mining height using
the SLS method from 20 m to 25 m where possible. |
| · | Mining
dilution. The mine should continue enhancing its blasting practices to minimize excessive
host rock over breaking, which can lead to increased unplanned dilution. |
| · | Optimization
of plant based on metallurgical testwork results for mineralization located in the upper
levels of the mine. The operation has identified a decrease in metallurgical recovery
by approximately 5 % associated with mineralization from the upper levels of the mine, which
recent mineralogical analysis indicates is related to the presence of hematite (iron-oxide).
Additional metallurgical testwork has been initiated with results expected by the end of
March 2024. Based on these results, it is recommended that the processing methodology
is optimized to maximize metallurgical recovery by processing this mineralized material in
batches. The budgeted cost of these tests is US$ 10,000. |
December 31, 2023 | Page 29 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
This Technical
Report (the Report) on the San Jose Mine in Oaxaca, Mexico (the San Jose Mine or the Project), has been prepared by Mr Eric Chapman,
P. Geo., Mr Paul Weedon, MAIG, Mr Raul Espinoza, FAusIMM (CP), Mr Veillette, P. Eng., and Ms Gonzalez, MMSA (QP), for Fortuna
Silver Mines Inc. (Fortuna) in accordance with the disclosure requirements of Canadian National Instrument 43-101 – Standards
of Disclosure for Mineral Projects (NI 43-101). The Report discloses updated Mineral Resource and Mineral Reserve estimates for the
San Jose Mine.
The mineral rights of the San Jose Mine
are held by Compania Minera Cuzcatlan S.A. de C.V. (Cuzcatlan). Cuzcatlan is a Mexican subsidiary that is 100 % indirectly owned by Fortuna
and is responsible for operating the San Jose Mine.
The following Qualified Persons are responsible
for Report preparation:
Mr. Eric Chapman, P. Geo. Senior
Vice President of Technical Services - Fortuna Silver Mines Inc.
Mr. Paul Weedon, MAIG, Senior Vice
President of Exploration - Fortuna Silver Mines Inc.
Mr. Raul Espinoza, FAusIMM (CP),
Director of Technical Services Fortuna Silver Mines Inc.
Mr. Mathieu Veillette, P.Eng., P.E.,
Director, Geotechnical, Tailings and Water – Fortuna Silver Mines Inc.
Ms. Patricia Gonzalez, MMSA (QP),
Director of Operations – Compania Minera Cuzcatlan S.A. de C.V.
| 2.3 | Scope
of personal inspection |
Mr. Eric Chapman has visited the
property on multiple occasions since 2011, most recently from November 14 to 15, 2023. During his site visits, Mr. Chapman
has reviewed data collection, drill core, storage facilities, database integrity, procedures, and geological model construction. Discussions
on geology and mineralization were held with Cuzcatlan personnel, and field site inspections were performed including a review of underground
geology of the Trinidad Deposit, and inspection of operating drill machines. He worked with site geological personnel reviewing aspects
of data storage (database) and analytical quality control.
Mr. Paul
Weedon has visited the mine on multiple occasions, most recently from August 11 to 13,
2023. During these visits, Mr. Weedon has reviewed drilling performance, sample and data collection, site QAQC records and geological
model development for the San Jose Mine mineralization.
Mr. Raul Espinoza conducted a site
visit to the property on December 4 to 6, 2023. During this visit Mr. Espinoza reviewed current mining methods, road access,
and discussed the Mineral Reserve estimation methodology, operating and capital expenditure requirements with Cuzcatlan personnel.
December 31, 2023 | Page 30 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Mr. Mathieu Veillette most
recently visited the property from October 31 to November 2, 2023, where he performed a field visit on the partially
closed downstream raised conventional tailings facility, dry stack tailings facility, waste dumps and water management facilities.
He also reviewed and discussed with site personnel designs and procedures for the tailings facilities, waste dumps, geotechnical
models, water balance and closure plan.
Ms. Patricia Gonzalez has been continuously
employed by Cuzcatlan since 2011, occupying various supervisory roles at the San Jose Mine operations including plant superintendent.
Ms. Gonzalez reviews daily reports detailing metallurgical performance as well as the monthly and quarterly metallurgical balance.
Ms. Gonzalez is also responsible for reviewing and approving any adjustments to the process design or metallurgical testwork programs
while her day-to-day activities include verifying plant operations, overseeing installation of new equipment, fine-tuning the current
operational strategy, and discussing aspects of mineralogy, lithology and operational issues with the site staff.
Ms. Gonzalez also works closely
with the relevant departments to execute the necessary environmental and community programs as part of Fortuna’s Environmental,
Social, and Governance (ESG) criteria.
The Report has a number of effective
dates, as follows:
| · | June 30,
2023: date of database cut-off for assays used in the Mineral Resource estimate for the San
Jose Mine. |
| · | December 31,
2023: date of the Mineral Resource and Mineral Reserve estimate for the San Jose Mine, taking
into account production related depletion to this date. |
| · | December 31,
2023: date to which drilling has been reported. |
The overall effective date of the Report
is the date of the most recent supply of information on the ongoing drilling program, and the date of the Mineral Resource and Mineral
Reserve estimates, being December 31, 2023.
| 2.5 | Previous
technical reports |
Fortuna has previously filed technical
reports on the San Jose Mine, listed in reverse chronological order:
| · | Chapman,
E.N., & Sinuhaji, A., 2019. Technical Report on the San Jose Mine, Oaxaca, Mexico,
prepared for Fortuna Silver Mines Inc., effective date 22 February 2019. |
| · | Chapman,
E.N., & Gutierrez, E., 2017. Amended Technical Report on the San Jose Property,
Oaxaca, Mexico, prepared for Fortuna Silver Mines Inc., effective date 20 August 2016. |
| · | Chapman,
E.N., & Kelly, T.E.M., 2013b. Technical Report on the San Jose Property, Oaxaca,
Mexico, prepared for Fortuna Silver Mines Inc., effective date 22 November 2013. |
December 31, 2023 | Page 31 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
| · | Chapman
E.N., & Kelly, T.E.M., 2013a. Technical Report on the San Jose Property, Oaxaca,
Mexico, prepared for Fortuna Silver Mines Inc., effective date 22 March 2013. |
| · | Bow,
C.S., Chlumsky, G., & Milne, S., 2010. NI-43-101 Technical Report: San Jose Silver
Project, Oaxaca, Mexico. Technical report prepared by Chlumsky, Armbrust & Meyer
LLC (CAM) for Fortuna Silver Mines Inc., effective date 31 March 2010. |
| · | Lechner,
M., & Earnest, D., 2009. Mineral Resource Estimate, Trinidad Deposit, San Jose Project,
Oaxaca, Mexico. Technical report prepared by Resource Modeling Inc. and Resource Evaluation
Inc., for Fortuna Silver Mines Inc., effective date 10 December 2009. |
| · | Hester,
M., & Ray, G., 2007. Geology, Epithermal Silver-Gold Mineralization and Mineral
Resource Estimate at the San Jose Mine Property, Oaxaca, Mexico. Technical report prepared
by Independent Mining Consultants Inc. (IMC), for Fortuna Silver Mines Inc., effective date
31 March 2007. |
| · | Ray,
G., 2006. Geology and Epithermal Silver-Gold Mineralization at the San Jose and the Taviche
Properties, Oaxaca, Mexico. Technical report prepared for Fortuna Silver Mines Inc., effective
date 12 March 2006. |
A technical report was filed by Continuum
Resources Ltd (Continuum) in 2004:
| · | Osterman,
C., 2004. Geology and Silver-Gold Mineralization at the San Jose Mine and the Taviche Mining
District, Oaxaca, Mexico. Technical Report prepared for Continuum Resources, effective date
2 December 2004 |
| 2.6 | Information
sources and references |
The main information source referenced
in this Report is the 2019 technical report:
| · | Chapman,
E.N., & Sinuhaji, A., 2019. Technical Report on the San Jose Mine, Oaxaca, Mexico,
prepared for Fortuna Silver Mines Inc., effective date 22 February 2019. |
Additional information was obtained from
site personnel including mine planning from Jose Luis Solorzano (Technical Services Manager), mine geology from Jose Blanco (Manager
of Mine Geology), exploration from Alejandro Chavez (Director of Brownfields Exploration), metallurgical input from Aldo Curiel (Plant
Superintendent), legal from Lucia Hurtado (Director, Legal), social, environmental and permitting guidance from Cristina Rodriguez (Director
of Sustainability).
Some of the more commonly used acronyms
used in the Report are detailed in Table 2.2.
December 31, 2023 | Page 32 of 208 |
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Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Table 2.1 Acronyms
Acronym |
Description |
Acronym |
Description |
Ag |
silver |
Moz |
million
troy ounces |
Ag
Eq |
silver
equivalent |
MVA |
megavolt
ampere |
Au |
gold |
MXN$ |
Mexican
pesos |
cfm |
cubic
feet per minute |
NI |
National
Instrument |
cm |
centimeters |
nm |
nanometers |
COG |
cut-off
grade |
NPV |
net
present value |
Cu |
copper |
NSR |
net
smelter return |
CV |
coefficient
of variation |
OK |
ordinary
kriging |
dmt |
dry
metric tonne |
oz |
troy
ounce |
g |
grams |
ppm |
parts
per million |
g/t |
grams
per metric tonne |
Pb |
lead |
ha |
hectare |
QAQC |
quality
assurance/quality control |
hp |
horsepower |
QQ |
quantile-quantile |
kg |
kilogram |
RMR |
rock
mass rating |
kg/t |
kilogram
per metric tonne |
RQD |
rock
quality designation |
km |
kilometer |
SD |
standard
deviation |
koz |
thousand
troy ounces |
SMU |
selective
mining unit |
kPa |
kilopascal |
t |
metric
tonne |
kV |
kilovolt |
t/m3 |
metric
tonnes per cubic meter |
kVA |
kilovolt
ampere |
tpd |
metric
tonnes per day |
l |
liter |
yd |
yard |
IDW |
inverse
distance weighting |
yr |
year |
LOMP |
life-of-mine
plan |
Zn |
zinc |
m |
meter |
U$S/t |
United
States dollar per metric tonne |
mm |
millimeter |
US$/g |
US
dollar per gram |
Ma |
millions
of years |
|
|
masl |
meters
above sea level |
|
|
December 31, 2023 | Page 33 of 208 |
| |
|
|
Fortuna
Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
| 3 | Reliance
on Other Experts |
The QPs have not independently reviewed
ownership of the San Jose Mine and any underlying agreements, mineral tenure, surface rights, or royalties. The QPs have fully relied
upon, and disclaim responsibility for, information derived from Fortuna and legal experts retained by Fortuna for this information through
the following documents:
| · | Rodriguez-Matus
and Feregrino Lawyers, 2024: Title Opinion Re: Mining Concessions San Jose Mine. Opinion
prepared for Fortuna Silver Mines Inc. and Compania Minera Cuzcatlan, S.A. de C.V. dated
February 7 2024. |
| · | Hurtado,
2024: Surface Rights and Environmental Liabilities of Compania Minera Cuzcatlan, S.A. de
C.V. as of January 31, 2024. Internal memorandum prepared for Fortuna Silver Mines Inc.,
dated February 7, 2024. |
This information is used in Section 4
of the Report. The information is also used in support of the Mineral Resource estimate in Section 14, the Mineral Reserve estimate
in Section 15, and the financial analysis in Section 22.
December 31, 2023 | Page 34 of 208 |
| |
| Fortuna Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico Technical Report |
4 | Property Description and Location |
The San
Jose Mine is located in the central portion of the state of Oaxaca, Mexico at latitude 16⁰41’39.10” N, longitude 96⁰42’06.32”
W; UTM coordinates NAD27, UTM Zone 14N: 745100E, 1846925N.
The mine
site is 47 km by road south of the city of Oaxaca and 0.8 km east of federal highway 175, the major highway between Oaxaca and Puerto
Angel on the Pacific coast. The village of San Jose del Progreso is located 2 km to the southeast of the mine site. The nearest commercial
center is the town of Ocotlan de Morelos, located approximately 12 km north of the mine site (Figure 4.1).
Figure
4.1 Map showing the location of the San Jose Mine
Figure
prepared by Cuzcatlan, 2023
December 31, 2023 | Page 35 of 208 |
| |
| Fortuna Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico Technical Report |
Fortuna
acquired a 100 % interest in the San Jose Mine in 2009. The property comprises mining concessions; surface rights; a permitted 3,000
tpd flotation plant; connection to the national electric power grid; as well as permits for the infrastructure necessary to sustain mining
operations.
| 4.1.1 | Mining claims and concessions |
The San
Jose Mine consists of mineral rights over 22 mining concessions for a total surface area of approximately 47,844 hectares (ha). A list
of the mining concessions showing the names, areas in hectares, and title details are presented in Table 4.1 with their location
shown in Figure 4.2. A six-monthly payment to Direccion General De Minas (DGM) is required to maintain the concessions. These payments
have been met and are current.
Table
4.1 Mineral concessions owned by Cuzcatlan
No. |
Concession Name |
Title |
Expiry date (D/M/Y) |
Municipality |
Area (ha)* |
1 |
Mioxa Uno |
179969 |
22/03/2037 |
San Miguel Tilquiapam |
24.00 |
2 |
Progreso III |
215254 |
13/02/2052 |
San Jose del Progreso |
283.39 |
3 |
Reduccion Taviche Oeste |
215542 |
04/03/2052 |
San Jerónimo Taviche |
6,254.00 |
4 |
Progreso II |
217624 |
05/08/2052 |
San Jose del Progreso |
53.88 |
5 |
Progreso II Bis |
217625 |
05/08/2052 |
San Jose del Progreso |
80.73 |
6 |
Progreso |
217626 |
05/08/2052 |
San Jose del Progreso |
284.00 |
7 |
Hueco |
221461 |
12/02/2054 |
San Jerónimo, Taviche |
41.78 |
8 |
El Pochotle |
224956 |
27/06/2055 |
San Jerónimo, Taviche |
1,313.00 |
9 |
Los Ocotes |
235074 |
23/11/2056 |
Ejutla de Crespo |
15,076.52 |
10 |
Bohemia Uno |
229343 |
10/04/2057 |
San Jerónimo, Taviche |
30.09 |
11 |
Bohemia Dos |
229344 |
10/04/2057 |
San Jerónimo, Taviche |
13.61 |
12 |
Bohemia Tres |
231370 |
11/02/2058 |
San Jerónimo, Taviche |
24.15 |
13 |
Victoria |
231995 |
02/06/2058 |
San Jerónimo Taviche |
643.86 |
14 |
Bohemia Cuatro |
232329 |
28/07/2058 |
San Jerónimo Taviche |
0.04 |
15 |
Los Ocotes Cinco Fracción I |
235699 |
15/02/2060 |
Ejutla de Crespo |
65.16 |
16 |
Cuzcatlan |
237918 |
29/06/2061 |
San Jerónimo Taviche |
11.39 |
17 |
Unificacion Cuzcatlan 5 |
241696 |
02/12/2053 |
San Jerónimo, Taviche |
198.16 |
18 |
Reduccion Unificacion Cuzcatlan 4 |
247050 |
16/01/2073 |
San Jerónimo, Taviche + 11 others |
10,318.05 |
19 |
Reducción Tlacolula 2 |
233392 |
21/11/2057 |
San Baltazar Chichicapam + 4 others |
12,642.00 |
20 |
La Voluntad |
218976 |
27/01/2053 |
San Jerónimo, Taviche |
279.04 |
21 |
Bonita Fraccion I |
218977 |
27/01/2053 |
San Jerónimo, Taviche |
26.14 |
22 |
Bonita Fraccion II |
218978 |
27/01/2053 |
San Jerónimo, Taviche |
181.19 |
Total |
47,844.20 |
*Areas rounded to two decimal places; total may differ from exact due to rounding process. |
December 31, 2023 | Page 36 of 208 |
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| Fortuna Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico Technical Report |
Figure
4.2 Location of mining concessions at the San Jose Property
Note: Numbers
represent concessions detailed in Table 4.1
Figure prepared by Cuzcatlan, 2023
As of December 31,
2023, the only concessions that contain Mineral Resources or Mineral Reserves are Progreso (No.6), Progreso II Bis (No.5), and Reduccion
Taviche Oeste (No. 3).
Cuzcatlan
has signed 45 usufruct contracts, which have been registered before the National Agrarian Registry, with landowners to cover the surface
area needed for the operation and tailings facilities (Table 4.2). The surface area can be divided into two parts, a north area covering
the operational footprint (54.58 ha), and a south area covering the area of the tailings storage facility (69.69 ha).
Cuzcatlan
has also entered into usufruct agreements (Not-Assigned Usufruct Agreements), regarding two parcels totaling 2.58 ha which are valid
and binding but do not have a parcel certificate and have not been duly assigned to their respective titleholders before the National
Agrarian Registry.
December 31, 2023 | Page 37 of 208 |
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| Fortuna Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico Technical Report |
Table
4.2 Usufruct contracts registered by Cuzcatlan for land usage at San Jose
No. |
Parcel No |
Landowner |
Area (ha) |
Type of contract |
Parcel Cert. |
Date Registered
(D/M/Y) |
Contract length (yrs) |
North (Mine area) |
1 |
1837 |
Ciriaco Torres Hernandez |
2.50 |
Usufruct |
177308 |
12/03/10 |
30 |
2 |
1441 |
Ricardo Ibarra Bosques |
0.91 |
Usufruct |
139851 |
28/01/10 |
30 |
3 |
1442 |
Ricardo Ibarra Bosques |
1.74 |
Usufruct |
139852 |
28/01/10 |
30 |
4 |
1467 |
Ricardo Ibarra Bosques |
2.53 |
Usufruct |
139850 |
28/01/10 |
30 |
5 |
1468 |
Vitaliano Munoz Rivera |
2.47 |
Usufruct |
107708 |
23/03/09 |
30 |
6 |
1475 |
Asuncion Gonzalez |
4.12 |
Usufruct |
178674 |
23/03/09 |
30 |
7 |
1836 |
Ubaldo Dionicio Ramirez |
1.82 |
Usufruct |
176683 |
28/10/10 |
30 |
8 |
1848 |
Valentin Dionicio Perez |
0.79 |
Usufruct |
176990 |
28/10/10 |
30 |
9 |
1558 |
Jose Dionicio Perez |
0.37 |
Usufruct |
176659 |
28/10/10 |
30 |
10 |
1649 |
Aristeo Gregorio Dionisio Perez |
0.45 |
Usufruct |
176656 |
28/10/10 |
30 |
11 |
1650 |
Vicente Emilio Dionicio Perez |
0.55 |
Usufruct |
176657 |
28/10/10 |
30 |
12 |
1840 |
Ubaldo Dionicio Ramirez |
0.56 |
Usufruct |
176685 |
28/10/10 |
30 |
13* |
1839 |
Nolberta Sanchez |
2.20 |
Usufruct |
177255 |
28/10/10 |
10 |
14 |
815 |
Fermin Delfino Ruiz |
0.30 |
Usufruct |
106628 |
28/10/10 |
30 |
15 |
1496 |
Olga Delfina Gonzalez Porras |
0.86 |
Usufruct |
176739 |
28/10/10 |
10 |
16 |
1495 |
Melecio Guadalupe Arrazola |
0.77 |
Usufruct |
176598 |
16/02/09 |
30 |
17 |
1492 |
Juan Sabas Arrazola Gopar |
0.61 |
Usufruct |
176601 |
16/02/09 |
30 |
18 |
1489 |
Mario Guadalupe Arrazola Gopar |
0.64 |
Usufruct |
176603 |
16/02/09 |
30 |
19 |
1436 |
Luis Munos Rivera |
1.79 |
Usufruct |
1044291 |
11/12/18 |
30 |
20** |
1443 |
Teodulfo Roman Vazquez |
2.94 |
Usufruct |
197698 |
25/08/21 |
10 |
21 |
1456 |
Martin Abelino Arango Merida |
8.21 |
Usufruct |
106845 |
20/04/09 |
30 |
22 |
1459 |
Joel Ramon Arango Merida |
4.75 |
Usufruct |
107368 |
23/03/09 |
30 |
23 |
1480 |
Ciriaco Torres Hernandez |
1.87 |
Usufruct |
177301 |
09/12/08 |
30 |
24 |
1509 |
Agustin Moises Sanchez Perez |
1.20 |
Usufruct |
206830 |
18/12/14 |
30 |
25 |
1498 |
Benedicto Fermin Gopar Ruiz |
5.20 |
Usufruct |
176772 |
20/02/18 |
30 |
26 |
1854 |
Pablo Ciriaco Ruiz |
4.43 |
Usufruct |
188870 |
06/08/19 |
19 |
South (Tailings storage facility) |
1 |
1516 |
Sixto Juan Sanchez |
0.10 |
Usufruct |
177247 |
29/05/14 |
12 |
2 |
1517 |
Pablo Ciriaco Gopar Ruiz |
11.83 |
Usufruct |
176783 |
23/03/09 |
30 |
3 |
1518 |
Agustin Rodrigo Sanchez Munoz |
1.68 |
Usufruct |
177260 |
10/06/09 |
30 |
4 |
1525 |
Fillberto Timoteo Ruiz Hernandez |
3.59 |
Usufruct |
177229 |
18/12/14 |
30 |
5 |
1526 |
German Martinez Arrazola |
0.54 |
Usufruct |
176915 |
28/01/10 |
30 |
6 |
1576 |
Eusebio Victor Martinez |
2.87 |
Usufruct |
176906 |
28/01/10 |
30 |
7 |
1579 |
Juan Arango |
6.00 |
Usufruct |
210567 |
15/08/17 |
10 |
8 |
1586 |
Benedicto Fermin Gopar Ruiz |
8.06 |
Usufruct |
176771 |
28/01/10 |
30 |
9 |
1587 |
Lilia Gopar Carreno |
1.75 |
Usufruct |
178700 |
16/02/09 |
30 |
10 |
1588 |
German Martinez Arrazola |
0.77 |
Usufruct |
176912 |
28/01/10 |
30 |
11 |
1593 |
Gonzalo Gopar Arango |
2.50 |
Usufruct |
176770 |
28/01/10 |
30 |
12* |
1616 |
Flora Maria Rodriguez Sanchez |
4.66 |
Usufruct |
177192 |
23/02/10 |
20 |
13* |
1617 |
Flora Maria Rodriguez Sanchez |
6.89 |
Usufruct |
177193 |
22/02/10 |
20 |
14 |
1625 |
Ciriaco Torres Hernandez |
2.00 |
Usufruct |
177307 |
29/05/14 |
15 |
15 |
1646 |
Bernardo Lopez Lopez |
9.01 |
Usufruct |
176871 |
28/01/10 |
30 |
16 |
1828 |
Diomedes Didimo Vasquez Sanchez |
1.25 |
Usufruct |
177436 |
29/09/15 |
30 |
17 |
1519 |
Laudelino Fermin Arrazola Gopar |
1.72 |
Usufruct |
178697 |
14/08/17 |
30 |
18 |
1508 |
German Martinez Arrazola |
2.04 |
Usufruct |
176917 |
14/08/17 |
30 |
19 |
1520 |
Aquilino Vasquez |
2.43 |
Usufruct |
177477 |
14/08/17 |
30 |
* The usufruct amendment agreements
of parcels 1839, 1496, 1616 and 1617 are in the process of registration at the National Agrarian Registry.
** An extension
agreement of parcel 1443 was executed with Teodulfo Román Vázquez on August 25, 2021, for an additional term of 10
years and is currently in the process of registration at the National Agrarian Registry.
December 31, 2023 | Page 38 of 208 |
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| Fortuna Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico Technical Report |
The San
Jose Mine is not subject to any back-in rights, liens, payments or encumbrances. The mineral tenure is subject to the following royalties:
| · | Royalty
agreement between Cuzcatlan and Beremundo Tomas de Aquino Antonio dated July 1, 2007,
granting a 1 % net smelter return (NSR) royalty to a maximum of US$ 800,000 in regard
to the mining concession “El Pochotle” listed as number 8 in Table 4.1. To date
no mineralized material has been extracted from the El Pochotle concession and no Mineral
Resources or Mineral Reserves have been identified on the El Pochotle concession. Cuzcatlan
has a buyout provision whereby the company can purchase this royalty right for US$ 200,000. |
| · | Royalty
agreement between Cuzcatlan and Underwood y Calvo Compania, S.N.C dated June 22, 2006,
granting a 1 % NSR royalty to a maximum of US$ 2,000,000 with regards to the mining
concessions “La Voluntad”, “Bonita Fraccion I” and “Bonita
Fraccion II” listed as numbers 20 to 22 in Table 4.1. To date no mineralized material
has been extracted from these concessions and no Mineral Resources or Mineral Reserves have
been identified in the concessions. Cuzcatlan has a buyout provision whereby the company
can purchase this royalty right for US$400,000. |
| · | Royalty
agreement between Cuzcatlan and Pan American Silver dated January 30, 2013, granting
a 1.5 % NSR royalty to Plata Panamericana S.A. de C.V., which was subsequently transferred
to Maverix Minerals Inc., and a 1 % NSR royalty to the Mexican Geological Service (SGM) as
a Discovery Royalty in regards to the mining concession “Reduccion Taviche Oeste”,
listed as number 3 in Table 4.1. |
| · | Royalty
agreement between Cuzcatlan and Geometales de Norte, S.A. de C.V. dated July 31, 2017,
granting a 2 % NSR royalty with regards to the mining concession “Reduccion Tlacolula
2”, listed as number 19 in Table 4.1. Cuzcatlan has the right to purchase 50 % of the
royalty for US$ 1,500,000. |
| · | Royalty
agreement between Cuzcatlan and the SGM dated March 18, 2022, granting a 3 % NSR royalty
with regards to the mining concession “Progreso”, listed as number 6 in Table
4.1. |
Royalties
held by SGM on the Hueco, La Voluntad and Unificacion Cuzcatlan 5 concessions are disputed by Fortuna on the basis that there was no
legal basis for the creation of such royalties, and they were invalidly created. No ore is currently being extracted from these concessions
and no legal action has been initiated by SGM.
Royalties
that affect the Mineral Reserves and are included in the economic analysis are:
| · | A
1.5 % royalty to Maverix on the Reduccion Taviche Oeste concession. |
| · | A
3 % royalty on the Progreso concession and a 1 % royalty the Reduccion Taviche Oeste concession
payable to SGM. |
On January 1,
2014, a Tax Reform package (the Reform), as presented by the Executive Branch of the Mexican government, came into force. Under the Reform,
the following taxes are applicable to the San Jose Mine:
December 31, 2023 | Page 39 of 208 |
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| Fortuna Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico Technical Report |
| · | Special
Mining Fee. This is a 7.5 % royalty on earnings before interest and taxes (EBIT), which covers
income minus producing costs, however, some costs will no longer be deductible. |
| · | Extraordinary
Mining Fee, consisting of a 0.5 % rate for companies producing gold, silver and platinum.
This fee is based on the gross revenues derived from the sales of these metals. |
The taxes
are calculated at year-end with Cuzcatlan paying an average of 40 million Mexican pesos per year since 2014. A proportion of exploration
expenses can be deducted from these taxes based on approved accounting methods.
The San
Jose del Progreso area has a long history of mining activity, including small-scale and artisan operations dating back to the 1800s.
There is an expectation that some environmental damage will have resulted from these activities.
| 4.4.1 | Term extension of EA 1731-2009 |
After a
request for the extension of the EIA was submitted to SEMARNAT in May 2021, the authority granted a 12-year extension of the EIA,
and formally notified Cuzcatlan on December 16, 2021. The EIA expires on December 17, 2033.
Despite
the above, on January 28, 2022, the Company received a notice (the Notice) from SEMARNAT that advised that it had made a typographical
error in the extension to the term of the EIA and that the correct term is two years.
On February 3,
2022, Cuzcatlan initiated legal proceedings in the Federal Court to challenge and revoke the typographical error and to reconfirm the
12-year extension period granted by SEMARNAT in December 2021.
On October 24,
2022, the Mexican Federal Administrative Court resolved the nullity trial in favor of Cuzcatlan and re-confirmed the term of the EIA
for a period of 12 years.
On January 2,
2023, SEMARNAT served Cuzcatlan with a resolution which annulled the EIA extension and stated that it was reassessing the 12-year EIA
extension.
Cuzcatlan
challenged the annulment of the EIA via a nullity trial presented before the Federal Administrative Court in Mexico City on January 10,
2023. Cuzcatlan obtained provisional and permanent injunctions from the Court which allowed the San Jose Mine to continue to operate
under the terms of the 12-year EIA. On October 30, 2023, Fortuna announced that the Federal Administrative Court had ruled in favor
of Cuzcatlan and re-instated the 12-year EIA for the San Jose Mine.
The decision
of the Mexican Administrative Court has been appealed and was admitted by the Collegiate Court in January 2024. Cuzcatlan filed
a response with the Collegiate Court in February 2024. A decision of the Collegiate Court is expected within the next six to 12
months. The permanent injunction that Cuzcatlan already has remains in effect.
Cuzcatlan
has an environmental commitment related to the remediation of the current mining facilities located on the Progreso and Reduccion Taviche
Oeste concessions. Cuzcatlan is to set aside US$ 6.5 million to cover remediation and closure requirements. These programs
are ongoing with funds assigned to various projects on an annual basis. Further details of the mine closure plan are included in Section 20.
December 31, 2023 | Page 40 of 208 |
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| Fortuna Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico Technical Report |
| 4.4.3 | Other risks or liabilities |
Cuzcatlan
has no knowledge of any further material risks or material environmental liabilities related to any of the other concessions connected
with the Project.
Section 20
provides additional information on the environmental status of the operation.
To the
extent known, all permits that are required by Mexican law for the mining operation have been obtained (see discussion in Section 20).
In the
opinion of the QPs:
| · | Fortuna
was provided with a legal opinion that supported that the mining concessions held by Cuzcatlan
for the San Jose Mine are valid and that Fortuna has a legal right to mine the deposit. |
| · | Fortuna
was provided with an internal legal memorandum that supported that the surface rights held
by Cuzcatlan for the San Jose Mine are in good standing. The surface rights are sufficient
in area for the mining operation infrastructure and tailings facilities. |
| · | Fortuna
was provided with a legal opinion that outlined royalties payable for the concessions held
by Cuzcatlan. |
| · | The
San Jose Mine is in full compliance with all material environmental laws and continues to
operate under the terms of the EIA that was approved on December 17, 2021. |
Fortuna
advised the QPs that to the extent known, there are no other significant factors and risks that may affect access, title or right or
ability to perform work at the mine. The information discussed in this section supports the declaration of Mineral Resources. Mineral
Reserves and the development of a mine plan with an accompanying financial analysis.
December 31, 2023 | Page 41 of 208 |
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| Fortuna Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico Technical Report |
| 5 | Accessibility, Climate, Local Resources, Infrastructure
and Physiography |
The
San Jose Mine is located 0.8 km east of Mexico federal highway 175, the major highway between Oaxaca and Puerto Angel on the Pacific
coast. The mine is 47 km, or one hour by road from the city of Oaxaca, which provides access to an international airport. Ocotlan, a
town of approximately 10,000 people and the nearest commercial center, is located 12 km to the north of the San Jose Mine along highway
175. The mine site is situated 2 km to the northwest of San Jose del Progreso, a village of approximately 2,500 people. Access within
the concessions is achieved via a network of unsealed roads and farm tracks.
The local
climate in the San Jose Mine area is temperate with temperatures generally ranging from 9ºC to 31ºC with an average annual
temperature of 19.5ºC. The lowest temperature recorded in the Project area was 4.1ºC in the month of January. The highest temperature
recorded was 35.4ºC in April. Average annual precipitation in the Project area ranges from 500 mm to 750 mm, with nearly all rain
occurring from April to October.
Mining
operations are conducted on a year-round basis.
|
5.3 | Topography,
elevation and vegetation |
The San
Jose Mine area is characterized by gently sloping hills and adjoining colluvial-covered plains.
Elevations
above mean sea level range from approximately 1,540 m to 1,675 m.
The vegetation
is grasslands and thornbush that are typical of dry savannah climates.
The operation
has a relatively small surface infrastructure consisting primarily of the concentration plant, electrical power station, water storage
facilities, filtered dry stack tailings facility, tailings dam, stockpiles, and workshop facilities, which are connected by unsealed
roads. Additional structures located within the Project area include offices, dining hall, laboratory, core logging and core storage
warehouses. The tailings storage facility is located approximately 1,500 m to the southwest of the concentration plant.
Experienced
underground miners live in the nearby towns of Ocotlan and Oaxaca in addition to other local towns in the district and are transported
to the property by bus.
Water for
the process plant and mining operations is primarily sourced via recirculation activities, and where top up is required, from the tailings
storage facility.
The mine
facilities are connected to the main electrical power supply managed by the Federal Electricity Commission, which supplies sufficient
power for the operation. The mine also has a secondary power line in case of power failure in the main line.
More detailed
information regarding the Project infrastructure is provided in Section 18.
December 31, 2023 | Page 42 of 208 |
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| Fortuna Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico Technical Report |
|
5.5 | Sufficiency
of surface rights |
The San
Jose Mine infrastructure has a compact layout footprint as detailed in Section 18 of this Report. The mine’s processing facility
and supporting infrastructure is located well within the area of surface rights and mineral tenure owned by Cuzcatlan.
In the
opinion of the QPs, the existing infrastructure, availability of staff, the existing power, water, and communications facilities, the
methods whereby goods are transported to and from the mine site, and any planned modifications or supporting studies are well-established
and understood by Fortuna, and support the declaration of Mineral Resources and Mineral Reserves and the proposed mine plan.
There are
sufficient mineral tenure and surface rights held to support the life-of-mine plan (LOMP) and mining operations on a year-round basis.
December 31, 2023 | Page 43 of 208 |
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| Fortuna Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico Technical Report |
The San
Jose Mine is located in the Taviche Mining District of Oaxaca, Mexico. The earliest recorded activity in the San Jose del Progreso area
dates to the 1850s when mines were exploited on a small scale by the local hacienda (Alvarez, 2009). By the early 1900s, a large number
of silver- and gold-bearing deposits were being exploited in the San Jeronimo Taviche and San Pedro Taviche areas, aided by a new mining
law enacted in 1892 and with support from foreign investment capital (Carranza Alvarado et al, 1996). Mining activity in the district
diminished drastically with the onset of the Mexican Revolution in 1910, only to resume sporadically in the 1920s. Mining in the San
Jose area was re-activated on a small scale in the 1960s and again in 1980 when the San Jose Mine was acquired by Ing. Ricardo Ibarra.
The mine was worked intermittently by Ibarra through his company Minerales de Oaxaca S.A. (MIOXSA) through to the end of 2006 when the
property was purchased by Compania Minera Cuzcatlan S.A. de C.V., a Mexican-registered company owned jointly by Fortuna and Continuum
Resources Ltd. (Continuum).
In 1999,
the property was optioned by Pan American Silver and five core drill holes totaling 1,093.5 m were completed in the San Jose vein system.
Three of the drill holes were located in the vicinity of the Trinidad shaft and two were located along the southern extension of the
vein system in the San Ignacio area. Two of the three drill holes located in the vicinity of the Trinidad shaft intercepted strong silver
and gold mineralization over drill hole intervals ranging from 2.7 m to 25.6 m. The two drill holes located in the San Ignacio area intercepted
low to moderate grade silver-gold mineralization over narrow to moderate vein widths.
In March 2004,
Continuum, an exploration company based in British Columbia, Canada, completed an option agreement with MIOXSA covering 19 concessions
in the San Jose and San Jeronimo Taviche areas. Continuum conducted extensive chip-channel sampling in the underground workings of the
Trinidad deposit as well as 15 surface core drill holes totaling 4,877 m. Thirteen of the drill holes were located in the Trinidad area
and two were located in the San Ignacio area. Nine of the 13 drill holes completed in the Trinidad area intersected moderate to strong
silver–gold mineralization over significant vein widths. The two drill holes in the San Ignacio area intercepted low-grade silver–gold
mineralization over narrow widths.
In November 2005,
Fortuna reached an agreement with Continuum to earn a 70 % interest in Continuum’s interests in the properties optioned from MIOXSA
and assumed project management.
During
2006, Fortuna completed 38 core drill holes totaling 12,182 m in the San Jose project area with 25 of the drill holes located in
the Trinidad zone and 13 of the drill holes located in the San Ignacio area. In November 2006, Fortuna and Continuum purchased a
100 % interest in the properties from MIOXSA and simultaneously restructured their joint operating agreement to a 76 % interest for Fortuna
and a 24 % interest for Continuum.
During
2007, Fortuna (operating as Cuzcatlan) drilled 66 core drill holes totaling 26,586 m and in 2008/early 2009 Cuzcatlan completed 112 core
drill holes totaling 32,915 m.
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In March 2009, Fortuna completed the acquisition of all issued and outstanding shares of Continuum,
resulting in a 100 % ownership of the San Jose Project.
Since 2009,
an additional 1,212 drill holes totaling 383,163 m have been completed in the San Jose concessions from both surface and underground
drill stations.
From 1980
through 2004, production by MIOXSA was intermittent and came primarily from existing stopes and from development of the fourth and fifth
levels of the San Jose Mine. In 2005 and 2006, the sixth level was developed and mined with grades reported to range between 350 to 500
g/t Ag and 1.8 to 3.5 g/t Au. The mineralization was mined primarily from the Bonanza and Trinidad veins and extracted at rates of approximately
100 tpd through the Trinidad shaft. The 4 m by 4 m Trinidad shaft is developed to a depth of 180 m from the surface although
no horizontal development had taken place on the seventh level. The principal mining method used by MIOXSA was shrinkage stoping. The
mineralized material was processed at a small crushing and flotation plant in San Jeronimo de Taviche, located approximately 19 km by
paved and gravel roads from the San Jose Mine. The majority of the workers in the mine and plant were from the San Jeronimo de Taviche
area. High-grade concentrates were shipped by 30 t capacity trucks to the MET-MEX Penoles smelter at Torreon, Coahuila, Mexico. Concentrate
grades typically ranged from 9,000 g/t to 12,000 g/t Ag and 100 g/t to 140 g/t Au (Alvarez, 2009). Reliable estimates of the total production
during MIOXSA’s tenure are not available.
Commercial
production commenced under the management of Cuzcatlan on September 1, 2011 (Fortuna, 2011). A summary of total production figures
by year from September 2011 through December 31, 2023, is detailed in Table 6.1.
Table
6.1 Production figures during Cuzcatlan management of the San Jose Mine
Production |
2011* |
2012 |
2013 |
2014 |
2015 |
2016 |
2017 |
2018 |
2019 |
Ore processed (t) |
125,301 |
369,022 |
456,048 |
676,959 |
717,505 |
905,467 |
1,070,791 |
1,040,478 |
1,068,722 |
Head grade Ag (g/t) |
144 |
188 |
194 |
226 |
234 |
228 |
238 |
260 |
252 |
Head grade Au (g/t) |
1.36 |
1.74 |
1.46 |
1.72 |
1.83 |
1.72 |
1.77 |
1.75 |
1.57 |
Production Ag (oz) |
490,555 |
1,949,178 |
2,527,203 |
4,396,760 |
4,928,893 |
6,124,235 |
7,526,555 |
7,979,634 |
7,868,478 |
Production Au (oz) |
4,622 |
17,918 |
19,031 |
33,496 |
38,526 |
46,018 |
55,950 |
53,517 |
48,880 |
* Commercial production commenced in September 2011 |
Production |
2020 |
2021 |
2022 |
2023 |
Total |
Ore processed (t) |
934,381 |
1,041,154 |
1,029,590 |
930,200 |
10,365,618 |
Head grade Ag (g/t) |
224 |
209 |
191 |
171 |
220 |
Head grade Au (g/t) |
1.38 |
1.29 |
1.14 |
1.06 |
1.51 |
Production Ag (oz) |
6,165,606 |
6,425,029 |
5,762,562 |
4,656,631 |
66,801,319 |
Production Au (oz) |
37,805 |
39,406 |
34,124 |
28,559 |
457,852 |
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| 7 | Geological Setting and Mineralization |
The San
Jose Mine is hosted by an andesitic to dacitic effusive volcanic sequence of presumed Paleogene age. Further to the east, these andesites
and dacites are overlain by silicic crystalline and lithic tuffs and ignimbrites corresponding to the Mitla Tuff Formation of Miocene
age. These Cenozoic volcanic sequences overlie two distinct tectonostratigraphic terranes or crustal blocks: the Oaxaca or Zapoteco terrane
and the Cuicateco or Juarez terrane. The Oaxaca terrane is characterized by granulite-facies metamorphic basement of Grenvillian age
overlain by Paleozoic and Mesozoic sedimentary sequences. The Juarez terrane is a west-dipping fault-bounded prism of strongly deformed
Jurassic and Cretaceous oceanic and arc volcanic rocks that structurally overlies the Maya terrane and underlies the Oaxaca terrane (Martinez-Serrano
et al, 2008).
The Cenozoic
volcanic rocks hosting the San Jose Mine are interpreted to be related to subduction along the predominantly convergent southern Mexico
plate boundary with the volcanic sequence having been deposited approximately contemporaneous with the initial volcanic events of the
Trans-Mexican Volcanic Belt (Figure 7.1).
Figure
7.1 Map of Oaxaca state showing approximate distribution of Cenozoic volcanic rocks and underlying tectonostratigraphic terranes
Figure prepared by Cuzcatlan, 2015 after Ortega-Gutierrez (1988) and Ortega-Gutierrez et al. (1992).
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The San
Jose Mine area is underlain by a thick sequence of presumed Paleogene-age andesitic to dacitic volcanic and volcaniclastic rocks, which
in turn, discordantly overlie units ranging from orthogneisses and paragneisses of Mesoproterozoic age, limestones and calcareous sedimentary
rocks of Cretaceous age and continental conglomerates of the Early Tertiary Tamazulapan Formation (Figure 7.2; Dickinson and Lawton,
2001; Sanchez Rojas et al., 2003; Martinez-Serrano et al., 2008). In the Taviche area, the Paleogene-age volcanic rocks are intruded
by granodiorite to diorite stocks of possible Neogene age.
Figure
7.2 Local geology of the San Jose Mine area
Figure
prepared by Cuzcatlan, 2019, adapted from Sanchez Rojas et al. (2003).
Note: Not all exploration targets and mines shown are owned by
Fortuna.
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The San
Jose Mine area is underlain by a thick sequence of sub-horizontal andesitic to dacitic volcanic and volcaniclastic rocks of presumed
Paleogene age (Figure 7.3). These units have been significantly displaced along major north- and northwest-trending extensional fault
systems with the precious metal mineralization being hosted in hydrothermal breccias, crackle breccias, and sheeted stockwork-like zones
of quartz–carbonate veins emplaced within zones of high paleo-permeability associated with the extensional structures.
Figure
7.3 Geology of the San Jose Mine area
Note: Lithology code detailed in Figure 7.4
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A detailed
stratigraphic section of the volcanic and volcaniclastic units present in the San Jose Mine area has been developed through surface mapping
and detailed drill core logging of (Figure 7.4).
Figure
7.4 Stratigraphic column of the San Jose Mine area
Figure
prepared by Cuzcatlan, 2023
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In general,
the upper 650 to 700 m of the volcanic sequence is characterized by a series of distinct effusive andesitic to dacitic lava flow units
intercalated with thin but laterally extensive horizons of reddish-brown to grayish-brown volcaniclastic rocks. The andesitic to dacitic
flow rocks comprise coherent and autoclastic facies with classic volcanic textures indicating sub-aerial to subaqueous deposition of
the flow units. Poorly-sorted monomictic to polymictic autobreccias are commonly present at the base of the flow units and grade upward
to jigsaw-fit breccias and fractured coherent facies lava flows. Flow foliations are commonly observed in coherent facies lavas and generally
are subhorizontal to moderately inclined in orientation. Well preserved hyaloclastite breccias and in situ hyaloclastites are present
throughout the effusive sequence, having been formed by the non-explosive fracturing and disintegration of quenched lavas emplaced into
subaqueous settings. Blocky clasts with curviplanar surfaces and chloritized clast margins after glass are commonplace in the hyaloclastites.
Thin reddish-brown to grayish-brown stratified volcaniclastic units present between the major flow units and locally within the PAF-30
unit are interpreted to be the re-sedimented fines of the hyaloclastite breccias.
The lower
250 to 300 m of the volcanic sequence is characterized by intercalated pyroclastic deposits, stratified volcaniclastic sedimentary rocks,
and locally coherent lava flow facies.
The top
of the metamorphic basement unconformably underlying the Tertiary volcanic sequence has been intercepted in the footwall of the Trinidad
vein at an elevation of approximately 600 masl, by two drill holes in the far north of the Trinidad deposit and in the hanging wall with
one drill hole at elevation 455 masl. Regionally, the metamorphic basement consists of a quartz-feldspathic orthogneiss of granulite
facies (Ortega Gutiérrez, 1981; Mora et al., 1986; and Consejo de Recursos Minerales, 1996). A detailed petrographic analysis
of the rocks comprising this unit at the San Jose Mine was carried out in 2022 and indicated an amphibolite facies meta-granite of quartz-feldspathic
affinity (Brandt Engineering & Microanalysis, 2022).
The San
Jose Mine is located at the southern edge and western side of the long-lived regional Oaxaca fault and graben (Eocene to present day),
which was reactivated as a strong range boundary graben fault in the Oligocene–Miocene (Albinson, 2018). The kinematic interpretation
for the deposit is linked to a hybrid extensional shear zone defining extensional veins in a conjugate array related to left lateral
shearing with right-stepping structures prone to generating dilation zones. The kinematic model defines the precious metal mineralization
to be hosted by a steeply east-dipping, north- to north–northwesterly-trending structural corridor.
Silver
and gold mineralization in the Trinidad deposit is hosted by steeply-dipping hydrothermal breccias, crackle breccias and quartz–carbonate
veins emplaced along north- and northwest-trending, east–northeast-dipping, anastomosing brittle fault structures. These dominantly
dip-slip fault structures crosscut the sub-horizontal effusive flow and pyroclastic units, producing cumulative displacements ranging
to greater than 300 m between the footwall and the hanging wall of the mineralized structural corridor. Dilational zones occurring at
high angles to the dominantly dip-slip displacement vectors of the principal extensional fault systems are favored sites for vein or
stockwork vein emplacement.
Within
the mineralized structural corridor, fault zones are commonly extensively brecciated and seamed by fault gouge. Locally these zones are
strongly silicified and commonly display evidence of repeated brecciation and re-cementing. Northeast-trending post-mineral cross-
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faulting
is present locally with apparent sinistral displacement. In the hanging wall of the mineralized structural corridor, small-scale block
faulting is evidenced by the clear displacement of the reddish-brown volcaniclastic marker units.
|
7.4 | Description
of mineralized zones |
Precious
metal mineralization at the San Jose Mine is hosted by hydrothermal breccias, crackle breccias, quartz–carbonate veins and zones
of sheeted and stockwork-like quartz–carbonate veins emplaced along steeply-dipping north- and north–northwest-trending fault
structures.
The mineralized
structural corridor extends for greater than 3 km in a north–south direction (Figure 7.3) and has been divided into two sectors.
The Trinidad deposit area is located between 1846500N and 1847800N, and the San Ignacio area is located between 1845000N and 1846500N.
The Victoria mineralized zone is located approximately 350 m to the east of the Trinidad deposit.
According
to a fluid inclusion and petrographic study conducted by Albinson (2018), four main vein formation stages can be identified in the district:
| · | Stage
1. Early barren vein and black breccia defined by rounded to subangular fragments in
a finely-ground matrix of mylonitic character and fault-like fabric. Most of the fragments
consist of crystalline and jigsaw quartz with subordinate fragments of adularia, calcite
and wall-rock andesite. The rounded character of most of the fragments suggests explosive/diatreme
fluidization processes. The extensive brecciation at this stage indicates that a primitive
structure was followed by a protracted structural history which brecciated, silicified, and
sealed the original precursor vein material and breccias. Fluid inclusion determinations
define consistently low temperature quartz <200°C and low salinities <1.0 wt% NaCl. |
| · | Stage
2. Consists of multistage, banded quartz–adularia–calcite–sulfides.
This stage represents the main mineralizing event in the district and consists of multiple
complex sub-stages of adularia, and coarse quartz cemented by later jigsaw quartz with sulfides.
The multistage banding is considered a consequence of “crack and seal” processes
with coarse crystalline quartz reflecting sluggish deposition of prismatic quartz during
sealing periods and jigsaw quartz or finer crystalline quartz reflecting sudden opening,
more vigorous fluid flow accompanied or not by boiling, supersaturation of silica and deposition
of originally amorphous silica or finer crystalline quartz and metallic load. The fluid inclusion
analysis for this stage involves a zonation evolution in which the lowest temperatures and
salinities manifest upwards towards the historic near-surface Trinidad and San Ignacio sectors
with <250°C and under 2.0 wt% NaCl. The higher salinities are confined to the mid
and deep Trinidad orebodies indicating, although not conclusively, possible feeder zones
in the deep Trinidad vein north and south sectors. |
| · | Stage
3. Comprises barren coarsely crystalline quartz and some adularia as a multistage crack
and seal sequence. In some cases, this sequence can host scarce sulfides in earlier bands
meaning there is a possible transition between stages 2 and 3. The fluid inclusion analysis
for this stage consists of temperatures below 250°C and under 3.0 wt % NaCl. |
| · | Stage
4. Consists of barren, mostly white and blocky calcite that occur as dog-tooth crystals in vugs, or as crosscutting veinlets in the
earlier vein stages. Stage 4 |
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| | calcite
is consistent at a very low temperature (<200°C) and for the most part does not host measurable fluid inclusions. Salinities are
consistently under 1.0 wt% NaCl. |
The major
mineralized structures or vein systems recognized in the Trinidad deposit area are the Trinidad and Bonanza structures and the Stockwork
Zone. In addition to the major mineralized structures, secondary vein systems are present between the Trinidad and Bonanza systems and
locally in the hanging wall to the Bonanza system and also in the footwall to the Trinidad system. To-date, drilling has defined the
Trinidad and Bonanza mineralized structures over a strike length of approximately 1,300 m and to depths exceeding 600 m from the surface,
with average thicknesses of the veins ranging from 1.5 m up to 50 m in some areas of the main Stockwork Zone.
Acanthite
and silver-rich electrum are the primary silver- and gold-bearing minerals in the Trinidad Deposit. These minerals, together with pyrite,
are discontinuously interlayered with distinctively banded crustiform- and colloform-textured quartz, calcite and locally adularia. Classic
ginguro textures are present locally in the mineralized quartz–carbonate veins and hydrothermal breccias, with a close spatial
and genetic association between the acanthite and the silver- and gold-bearing electrum. The total sulfide content of the mineralized
structures is generally low, ranging from less than one volume percent to five volume percent of the rock in the upper portion of the
deposit and grading to somewhat higher sulfide contents at depth with the gradual introduction of sphalerite, galena and chalcopyrite.
Sphalerite is typically pale yellow–brown in color, being of the low iron variety.
Principal
gangue minerals are quartz and calcite, locally accompanied by iron or iron/magnesium-bearing carbonates. Amethyst and chalcedonic quartz
are commonly present as late infillings of the veins and hydrothermal breccias. Pale greenish-colored fluorite is locally present as
vein and breccia fillings.
Hydrothermal
alteration at the Trinidad deposit is characterized by a well-developed alteration zonation with kaolinite being present in the mineralized
zones grading outwards to kaolinite–illite, illite, and illite–smectite–chlorite assemblages. Locally iron-carbonates
and iron/magnesium-carbonates are also present as a halo to the mineralized zones. Regionally, the andesitic volcanic and volcanoclastic
units are weakly to moderately propylitically altered to epidote–chlorite–smectite assemblages (Figure 7.5).
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Figure
7.5 Trinidad and Victoria alteration assemblages and zonation
Silver equivalent calculated using a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and 91 % for Au
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Trinidad
vein system
The Trinidad
vein system (Tv) is emplaced in the footwall fault zone of the extensional system hosting the mineralized vein systems at the San Jose
Mine. The Trinidad vein system strikes 355 degrees and dips 70 to 80 degrees to the east–northeast. The vein system ranges from
less than one meter to locally over 15 m in true width, with higher grade mineralization generally being present in zones with greater
widths. Significant portions of the Trinidad structure are characterized by late, black matrix, silicified fault breccias with only trace
to weak mineralization. Combined copper, lead and zinc values are generally less than one percent, but locally higher concentrations
are present. At approximately 1,100 masl in the central portion of the Trinidad deposit, four drill holes intercepted higher-grade base
metal mineralization. Fault gouge seams are commonplace at the footwall and hanging wall of the Trinidad vein system. The Trinidad hanging
wall splays and the Trinidad footwall veins are considered to be part of the Trinidad mineralized structure.
Since late
2017, it has been observed that fluorine levels are not consistent throughout the Trinidad vein, with levels varying from 500 ppm in
the central and lower portions of the vein system to above 5,000 ppm and even 10,000 ppm in certain areas in the north. High fluorine
concentrations are generally, but not always, related to low silver–gold mineralization, and are thought to be related to a late
stage of mineralization. Stopes where the highest fluorine levels have been encountered include J, R, S, G1 and the northern part of
H1, located between elevations 1000 to 1300 masl.
Bonanza
vein system
The Bonanza
vein system (Bv) is emplaced in the hanging wall zone of the structural corridor hosting the mineralized vein systems in the Trinidad
deposit. The Bonanza vein system generally strikes 350 degrees and dips steeply to sub-vertical to the east. The Paloma vein (Pv) is
considered to be part of the Bonanza vein system. Mineralization within the Bonanza vein system is present in the form of shoots plunging
shallowly to moderately to the north-northwest, reflecting the dominant dip-slip movement of the controlling fault structures. Combined
copper, lead and zinc values for the Bonanza vein range from negligible in the upper portions of the vein system to approximately 0.1
to 0.5 % at depth.
Stockwork
Zone
The main
Stockwork Zone (Swk) is located between 1846425N to 1847825N and 1,460 masl to 800 masl, being situated in an extensional environment
between the principal Bonanza and Trinidad structures. The main Stockwork Zone is present over 1,400 horizontal meters and 660 vertical
meters being elliptical in shape, with a variable thickness ranging up to 75 m. Two cross-cutting faults have created a minor displacement
of the Stockwork Zone resulting in the mineralization being modeled via southern, central and northern portions.
The primary
silver-bearing mineral in the main Stockwork Zone is acanthite, usually in association with traces of pyrite. Secondary minerals accompanying
the acanthite are silver-rich electrum, fine-grained galena, sphalerite, chalcopyrite and gangue minerals including hyaline quartz, white
quartz, and calcite, together with minor concentrations of adularia and fluorite.
In addition
to the main Stockwork Zone, exploration has identified the Stockwork 2 (Swk2), Stockwork 3 (Swk3) and Stockwork 4 (Swk4) zones, located
in the north of the Trinidad deposit area between the Trinidad and Bonanza veins. Definition drilling has
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demonstrated that the Stockwork 2 and
Stockwork 3 zones are similar to the main Stockwork Zone and appear to be interconnected.
Fortuna vein system
The Fortuna vein (Fv) strikes north–south
and, in contrast to the other major veins in the Trinidad deposit, dips steeply to the west. The Fortuna vein has been extensively mined
on levels 2, 3 and 4 of the historic mine workings with vein widths ranging from approximately 2 to 5 m.
Other Trinidad vein systems
A number of other veins have been intersected
by exploration and definition drilling, as well as contributed to production. These include the Bonanza Hangingwall (Bhws), Trinidad Footwall
(Tfw), Trinidad Footwall 2 (Tfw2), Trinidad Footwall 3 (Tfw3), Trinidad Hanging Wall (Thws4), and Paloma veins.
The Bonanza Hangingwall vein is located in the
southern part of the Trinidad deposit, being a splay and closely connected to the Bonanza vein, with a strike of 323 degrees and a dip
of 80 degrees. The mineralized structure is generally narrow in nature, from about 1 to 6 m in width and extending for over 400 m along
strike between elevations 950 to 1,210 masl. This vein has been mined in conjunction with the Bonanza vein since 2015.
The Trinidad Footwall vein is located in the footwall
of the central–southern portion of the Trinidad vein, being generally connected and no more than 20 m west of the main structure.
The vein has a strike of 355 degrees and a dip of 85 degrees to the east and can reach 10 m in thickness. The vein is approximately 200
m in strike length and extends for approximately 120 m down dip between the 1,400 and 1,280 masl. This vein has been mined in conjunction
with the Trinidad vein since 2016.
The Trinidad FW2 vein is located in the northern
part of the Trinidad deposit, being a splay of the Trinidad vein at depth, striking 337 degrees and dipping 80 degrees. The mineralized
structure is narrow, being generally 1 to 2 m in width with a strike length of 400 m and extends for almost 500 m down dip between
elevations 1,480 to 1,000 masl.
The Trinidad FW3 vein is also located in the northern
part of the Trinidad deposit, being a splay of the Trinidad vein at depth with a strike of 332 degrees and dip of 82 degrees. The structure
is narrow, ranging from approximately 1 to 3 m in width, extending for 430 m along strike and is present between 1,480 to 1,000 masl.
The Trinidad Hangingwall vein is located in the
central part of the Trinidad deposit, being a splay of the Trinidad vein at upper levels and having a strike of 345 degrees and dip of
80 degrees. The mineralized structure varies between 1 and 6 m in width and extends for 160 m along strike between elevations 1,380 to
1,200 masl.
| 7.4.2 | Victoria mineralized zone |
The Victoria mineralized zone is located approximately
350 m east of the Trinidad vein and north of the current underground operations of the San Jose Mine. It is structurally related to the
same extensional regime that dominates the Trinidad deposit with a similar style of mineralization, corresponding to a low sulfidation
epithermal deposit formed in a shallow crustal environment with a relatively low temperature resulting in the precipitation of silver
and gold mineralization. Formation temperatures are believed to be on average less than 250°C with salinities less than 1.8 %wt
NaCl. Mineralization is hosted in breccias and quartz–carbonate veinlets with a general northwesterly direction and an approximate
dip of 70 degrees to the northeast. The dominant alteration within the structural system is
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argillic, grading to propylitic towards the
periphery. The hosting lithology is related to effusive volcanoclastic facies and flows of andesitic/dacitic rocks possibly of Paleogene
age.
The Victoria mineralized zone was discovered
in early 2015 during a drilling campaign directed towards the north of the Trinidad deposit to investigate potential mineralization at
the 1,300 m elevation. Two drill holes intersected silver equivalent values of interest related to the Victoria main structure. In the
second half of 2015, an initial program of exploration test drilling was conducted that targeted the Victoria mineralized zone, consisting
of six drill holes.
In 2016, a second program of drilling was conducted
to further delineate the extent of mineralization of the Victoria mineralized zone and, based on the positive results, additional exploration
drilling has been conducted since 2017 to support Mineral Resource estimation.
As of the effective date of this Report, the Victoria
mineralized zone has been defined over a strike length of 1,700 m and is known to dip over a vertical depth of approximately 550 m between
the elevations of 1,350 masl to 800 masl. Vein thickness ranges from 0.1 m up to 13.5m.
Victoria main structure
The Victoria main structure (Vmz) is defined by
a series of veins and veinlets, being structurally controlled over a broad zone of approximately 100 m. The mineralized part of the system
is comprised primarily of quartz-adularia-calcite-sulfides with low to medium concentrations of base metals being predominately sphalerite
and fine-grained chalcopyrite. There is a strong correlation between gold–silver mineralization and the presence of calcite, a similar
relationship that was observed in the upper levels of the Trinidad vein. Three mineralization stages have been identified in the Victoria
main structure.
| • | Stage 1 is characterized by narrow black breccias
perpendicular to the mineralized zone and are thought to act as the principal structural controls. |
| • | Stage 2 is related to high-temperature calcite
(260 °C to 280 °C), the presence of sulfides in the upper levels of the mineralized zone and is associated with precious metals.
Highly carbonatized wall rock suggests a peripheral style of mineralization. |
| • | Stage 3 is related to the presence of barren
multistage crack and seal quartz and is poorly understood. Stage 4 mineralization, present in the Trinidad deposit, is not observed in
the Vmz. |
The Vmz has been intersected the most out of the
identified structures of Victoria mineralized zone, with exploration drill programs carried out since 2019 establishing the controls on
mineralization and further defining the vertical and lateral extent of the silver–gold mineralization continuity.
Victoria hangingwall 1, 2 and 3 veins
The Victoria hangingwall 1, 2, and 3 veins (Vhw1,
Vhw2, and Vhwz3) are sub-parallel tensional splays consisting of veins/veinlets related to a graben-like downthrown block to the east
of the Victoria main structure. The dominant alteration style is propylitic, with the mineralization style being the same as that observed
in the Victoria main structure.
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Geologic sections
A representative series of sections displaying
the geological interpretation of the Trinidad deposit are presented in Figures 7.7 to 7.9 and of the Victoria mineralized zone in Figure
7.10. A plan view showing the location of the sections is provided in Figure 7.6. Silver equivalent (Ag Eq) values shown in the cross
sections have been estimated at a gold to silver ratio of 76, based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and
metallurgical recoveries of 92 % for Ag and 91 % for Au.
Longitudinal isograde sections for the Trinidad,
Bonanza, Stockwork, and Victoria main structure are presented in Figures 7.11 to 7.14, respectively.
In the opinion of the QPs, knowledge of the Trinidad
deposit and Victoria mineralized zone, the settings, lithologies, and structural and alteration controls on mineralization is sufficient
to support Mineral Resource and Mineral Reserve estimation.
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Figure 7.6 Plan map showing location
of resource drilling and orientation of sections
Footnote on veins: Bhws = Bonanza hangingwall; Bv = Bonanza; Swk =
Stockwork; Swk3 = Stockwork 3; Tv = Trinidad; Vmz = Victoria mineralized vein
Data cut-off date for Mineral Resource and Mineral Reserve estimation
is June 30, 2023 |
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Figure 7.7
Section displaying lithology along 1846925N
Silver equivalent calculated using a gold to silver ratio
of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and 91 % for Au
Lithology units detailed in stratigraphic column Figure 7.4 |
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Figure 7.8
Section displaying lithology along 1846975N
Silver equivalent calculated using a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and 91 % for Au
Lithology units detailed in stratigraphic column Figure 7.4
|
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Figure 7.9
Section displaying lithology along 1847500N
Silver equivalent calculated using a gold to silver ratio of
76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and 91 % for Au
Lithology units detailed in stratigraphic column Figure 7.4
|
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Figure 7.10
Section displaying lithology along 1848200N
Silver equivalent calculated using
a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and
91 % for Au
Lithology units detailed in stratigraphic column Figure
7.4 |
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Figure 7.11
Longitudinal section of Trinidad vein displaying Ag Eq isogrades
Silver equivalent calculated using
a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag
and 91 % for Au |
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Figure 7.12 Longitudinal section of
Bonanza vein displaying Ag Eq isogrades
Silver equivalent calculated using
a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and
91 % for Au
|
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Figure 7.13 Longitudinal section of
Stockwork mineralization Zones displaying Ag Eq isogrades
Silver equivalent calculated using
a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and
91 % for Au
|
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Figure 7.14
Longitudinal section of Victoria main structure displaying Ag Eq isogrades
Silver equivalent calculated using
a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and
91 % for Au
|
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The silver-gold deposits at the San Jose Mine
are typical of low-sulfidation epithermal deposits according to the classification of Corbett (2002), having formed in a relatively low
temperature, shallow crustal environment (Figure 8.1).
Figure 8.1
Classification of epithermal and base metal deposits
Figure prepared by Cuzcatlan, 2023, from Corbett
(2002) |
The deposits are characterized by structurally-controlled
hydrothermal breccias, crackle breccias and quartz–carbonate veins hosting silver–gold mineralization plus trace to minor
base metal mineralization. The Trinidad deposit is similar to the Fresnillo silver deposit in Zacatecas, Mexico and to precious metal
deposits located in the Altiplano Province of Southern Peru (Caylloma, Arcata, Pallancata deposits). Geologic characteristics of the Trinidad
deposit and Victoria structure are summarized in Table 8.1.
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Table 8.1
Trinidad deposit and Victoria mineralized zone characteristics
Characteristic |
Description |
Deposit Type |
Rift low sulfidation adularia-sericite epithermal deposit |
Regional Tectonic Setting |
Extensional continental margin-arc terrain |
Local Tectonic Setting |
Extensional fault system with plus 300 m normal displacement |
Host Rocks |
Andesitic to dacitic subaerial to subaqueous lava flows |
Host Rock Age |
Paleogene (?) |
Deposit Style |
Quartz-carbonate veins, hydrothermal breccias, crackle breccias, sheeted and stockworked vein zones |
Regional Alteration |
Regional propylitic alteration (chlorite > epidote) |
Deposit-scale Alteration |
Well crystallized kaolinite in mineralized zones grading outward to kaolinite-illite, illite and illite-smectite-chlorite assemblages; Fe- and Fe/Mg carbonates are present locally haloing the mineralization |
Main Metals |
Ag, Au |
Minor Metals |
Zn, Pb, Cu, Sb |
Main Sulfide Species |
Pyrite, Acanthite (Argentite), Low Fe Sphalerite, Galena, Chalcopyrite |
Silver-bearing Species |
Acanthite (Argentite), silver-rich electrum |
Gold-bearing Species |
Silver-rich Electrum |
Ag/Au Ratio |
Ranges from approximately 50 to 200 Ag to 1 Au |
Gangue Minerals |
Quartz, Calcite, Fe- and Fe/Mg carbonates, Mn Silicates and Carbonates |
Deposit Type Examples |
Fresnillo, Mx; Altiplano Province of Southern Peru (Caylloma, Arcata, Pallancata) |
The San Jose Mine is located within the Del Sur
crustal block of southern Mexico (Dickinson and Lawton, 2001). Oligocene to Pliocene-age andesitic to dacitic volcanic rocks disconformably
overlie Mesoproterozoic-age basement rocks comprised of orthogneisses and paragneisses that were stranded in their present positions when
the South America continent pulled away from the North America continent during the Middle Mesozoic breakup of Pangea. Epithermal-style
alteration and mineralization are widespread within the Middle to Late Tertiary volcanic package exposed throughout the central portion
of the state of Oaxaca. Host structures to the mineralization are normal faults and subsidiary structural features common to extension-related
pull-apart basins (Corbett, 2006) as illustrated in Figure 8.2.
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Figure 8.2 Exploration model: extension-related
pull-apart basins
Figure prepared by Cuzcatlan, 2023, from Corbett
(2006) |
The San Jose Mine is considered an example of
a low sulfidation epithermal-style deposit, based on the following:
| • | Low sulfidation adularia-sericite epithermal
environment. |
| • | Mineralization characterized by the presence
of quartz-carbonate veins, hydrothermal breccias, crackle breccias, sheeted and stockworked vein zones. |
| • | Alteration characterized by the presence of kaolinite
in mineralized zones grading outward to kaolinite–illite, illite and illite–smectite–chlorite assemblages. |
| • | Gold–silver mineralization present in the
form of acanthite (argentite) and silver-rich electrum. |
| • | Sulfides present in the form of pyrite, acanthite
(argentite), low Fe sphalerite, galena and chalcopyrite. |
Understanding of the geological setting of and
model concept for the San Jose system is adequate to provide guidance for mining and ongoing exploration activities.
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The Project area has a long history of exploitation
although formal exploration programs were not conducted in the area until 1999. Several exploration programs have since been conducted
by Pan American Silver, Continuum, and most recently Fortuna/Cuzcatlan.
| 9.1 | Exploration conducted by Pan American Silver |
In 1999, the San Jose Project was optioned by
Pan American Silver (Pan American). Surface and underground mapping and sampling were carried out by Pan American and five diamond drill
holes totaling 1,093.5 m were completed in the San Jose system.
| 9.2 | Exploration conducted by Continuum |
In March 2004, Continuum completed an option
agreement with MIOXSA covering 19 concessions in the San Jose and San Jeronimo Taviche areas. Continuum completed detailed mapping and
chip-channel sampling of the surface and of the existing underground workings in the Trinidad area followed by the completion of 15 surface
core drill holes totaling 4,876.55 m.
| 9.3 | Exploration conducted by Cuzcatlan |
Since 2007,
the principal exploration activities conducted include the following:
| • | Fluid inclusion and petrographic studies. |
| • | Drilling (described in Section 10). |
| • | Metallurgical testwork (described in Section 13). |
| • | Advanced spaceborne thermal emission and reflection
radiometer (ASTER) study. |
During the first half of 2017, Cuzcatlan signed
an agreement with the Servicio Geológico Mexicano to carry out a high resolution airborne magnetometric and gamma-ray spectrometric
study to define magnetic corridors that could represent alteration paths for mineral exploration. The survey covered an area of 132 km²
consisting of 80 east–west-oriented survey lines distributed 200 m apart, and perpendicular to the general trend of the Trinidad
system; and five north–south control lines, taken 2 km apart. Data were used in the Leapfrog 3D modeller software to identify generative
exploration targets.
A detailed magnetometric study was carried out
from 2019 to 2020 in the Taviche district to detect and determine structural lineaments using a drone and an EM DRONEmag ™, ultra
light-weight potassium magnetometer and a magnetometer GSM-19. A survey over 900 km was performed along cumulate lines oriented NE45°SW
with a separation of 50 m adding orthogonal secondary lines. The information has been used to improve the structural model of the district
to identify prospects that may warrant drilling.
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| 9.3.2 | Fluid inclusion and petrographic studies |
A petrographic and microprobe study was carried
out by Microscopía Electrónica y Aplicaciones en el Perú S.A.C. (MyAP), during 2014. The study involved the petro-mineragraphic
micro-analysis of 32 samples from the Trinidad deposit to determine textural relationships between mineral assemblages. The analysis defined
low to intermediate sulfidation mineralization of quartz–adularia–carbonates (dolomite–calcite). The economic mineralization
is related to acanthite–electrum–sphalerite–pyrite–galena–chalcopyrite and in minor proportions, native
silver-argentite–polybasite–jalpaite. The gangue minerals are mostly quartz, carbonates, adularia and traces of fluorite and
zeolites.
In the first half of 2018, Cuzcatlan hired an
external consultant to perform a combined fluid inclusion and petrographic study using optical microscopy on the mineralization and gangue
mineralogy and textures. A second study aim was a preliminary reconstruction of vein stratigraphy and of paleo-water tables during vein
formation. The program involved the analysis of 69 samples and reinterpretation of 150 previously taken samples by fluid inclusion analysis.
The final conclusions to the report (Albinson, 2018) identified four mineralization stages which reflect a protracted hydrothermal history
of the veins in the district (refer to summary in Section 7.4.1). The second paragenetic stage represents the main mineralizing event
responsible for high-grade mineralization in the vein systems. The periodic influx of high and low temperature fluids in stage 2 with
high salinities is closely associated with base metal and precious metal mineralization. The conclusions are considered important in helping
to identify potential exploration areas within the San Jose Project.
The Terraspec Halo™ equipment is a near
infra-red (NIR) and short wave infra-red (SWIR) frequency spectrometer operating between 300 and 2,400 nm and allows the identification
of alteration minerals (e.g., clay minerals, white micas, chlorites and carbonates) in real time.
The procedure for alteration analysis of drill
core is being carried out in two phases. Firstly, new core that is generated during ongoing drilling campaigns is analyzed, after being
logged and marked for geochemical sampling. The second phase involves the analysis of old core obtained from previous drilling campaigns
prior to the acquisition of the equipment. In both cases the process involves taking a reading from the core every 5 m using a calibrated
hand-held device, or when an interval has been marked for geochemical sampling. Once all the readings for a hole have been obtained, the
information is loaded into the database and spectral log reports are generated for each hole.
Terraspec analysis to measure alteration minerals
in the San Jose deposit began in August 2014 and became part of the systematic logging of all exploration drill holes. Holes drilled
prior to this date have been analyzed for alteration at a rate of 8,000 meters per year. As at the effective date of this Report, alteration
analysis has been completed on 57 % of the total holes drilled.
Surface mapping, at a scale ranging from 1:1,000
to 1:5,000, has identified numerous satellite systems within the Project area that at surface display potential for mineralization. The
location of the various exploration programs conducted by Cuzcatlan is displayed in Figure 9.1 and includes mapping of the San Ignacio,
Taviche (including El Rancho, El Pochotle, La Altona), La Noria, Maria, Los Diaz, and Victoria areas.
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Figure 9.1
Map showing location of exploration programs conducted by Cuzcatlan at the San Jose Mine
San Ignacio
The San Ignacio area is located 0.8 km south of
the San Jose Mine and is characterized by the presence of historical mining infrastructure connected to the north by old shallow workings
of the El Higo and La Santisima Trinidad mines, which represent the former San Jose Mine at elevations 1,500 masl to 1,600 masl. Previous
geological studies have been conducted in the San Ignacio area, as detailed in a technical paper published by the Consejo de Recursos
Minerales (1982). Underground mapping and sampling of historic mining areas of the San Ignacio area has not been possible due to accessibility
issues.
During 2009, Cuzcatlan conducted a detailed surface
mapping and sampling campaign in an area covering 800 m by 150 m, resulting in the detailed description of the lithostratigraphic effusive
units of the San Jose deposit (Section 7.3.1). The work also provided definition of the structural controls of the Trinidad system
to the south of the San Jose Mine as a complex family of predominantly north–south-oriented subparallel veins, a northwest-trending
secondary vein system, and a northeast-trending post-mineralized fault system. The sampling program returned irregular gold and silver
anomalies throughout the system.
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The fluid inclusion analysis conducted by Albinson
(2018) in conjunction with the geological mapping resulted in the conclusion that the San Ignacio veins located near surface represent
the geological level corresponding to possible roots or distal positions in the epithermal system, having precipitated in temperatures
below 250°C and low salinities (<3 wt% NaCl equivalent). An increase in the base metal content of the veins was observed.
Taviche
The Taviche area is located 13 km northeast of
the San Jose Mine and is the oldest historic mining district in the vicinity of the current operations. Mining activity conducted during
the 19th and 20th centuries exploited high-grade, shallow mineralization from mines such as San Juan and Conejo Blanco.
Despite the fact that several local geological-mining
reports were completed during the 20th century, no systematic exploration campaigns were recorded in the area until 2011 when exploration
efforts were conducted in the El Rancho area with a mapping at a scale of 1:2,000 and sampling program that covered 238 ha. This program
allowed Cuzcatlan to justify an exploration drill program that was completed in the last half of 2011.
During 2012, a detailed
mapping (1:1,000 scale) and sampling campaign covering 1,561 ha was conducted by Cuzcatlan defining a northwest–southeast-trending
structural corridor named El Pastal-Baldomero, which extended over 3 km. The programs identified the El Pastal, Baldomero, La Altona,
El Pochotle, La Esperanza and La Republica veins. From this field work a drilling program was completed to assess the La Altona and El
Pochotle veins in the second half of 2012.
Since 2022 a systematic mapping process has been
completed following recommendations derived from geophysical assessment, structural and lithological interpretations. The San Juan, El
Pastal, San Francisco and La Escuadra areas are being considered for drill testing.
La Noria
The La Noria prospect is located 2 km west of
the San Jose Mine and is related to a north–south-trending structural system of anastomosing veins subparallel to the Trinidad system.
Exploration conducted by Pan American in late 2006 supported a preliminary drill program conducted in 2007. The Pan American sampling
program involved the collection of 80 surface samples. In late 2014 and early 2015, Cuzcatlan followed this initial work with a detailed
mapping and sampling program covering 539 ha, taking 343 chip samples for geochemical analysis and 715 samples for alteration analysis.
This work led to targeted exploration drilling conducted by Cuzcatlan in late 2015 and 2016. This project defined discontinuous narrow
structures but did not identify economically viable mineralization.
Maria
The Maria area is located 2.5 km south of the
San Jose Mine and forms the southern continuity of the Trinidad structural system. Maria is interpreted as an area of potential anastomosed
tensional structures acting as kinematic indicators in the footwall of the Trinidad vein. Historical mine workings are present at the
Santa Maria shaft and associated waste dumps that contain anomalous levels of zinc, lead, silver, and copper. A systematic mapping and
sampling program conducted by Cuzcatlan in 2013 identified the southern extension of the Trinidad system to the El Portillo Mine (including
Maria) as a strategic target with the potential for mineralization. In 2017 Maria was drilled by Cuzcatlan to test for mineralization
at the confluence of the Maria and Trinidad veins. Results of the drilling defined possible dilation jogs at the junction of the Maria-Trinidad
structures with two holes intersecting narrow but economic grades. A further drill program planned for 2024
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will test the possible extension
of mineralization from the junction of these veins to the north.
Los Diaz
The potential of the Los Díaz area emerged
from data evaluation based on the analysis of geophysics and structural interpretations. The Trinidad deposit is located in the eastern
margin of a high magnetic susceptibility anomaly and Los Díaz represents a similar structural environment with the intersection
of two regional systems. A drilling program was undertaken in 2020 to test for possible mineralization in this region. The program confirmed
a domain of felsic dikes trending NW as well as discontinuous veinlets but with no significant results. Additional assessments are planned
for 2024 including high-resolution ground geophysics to determine the possible structural relationship of Los Diaz to the Victoria mineralized
zone.
Victoria mineralized zone
The Victoria mineralized zone was interpreted
at depth based on the location of a silicified outcrop to the north of the Trinidad deposit where the Trinidad vein is thought to converge
with a north–northwest-trending fault system associated with the Victoria mineralized zone. Exploration focused on drilling from
underground stations located in the Trinidad deposit eastwards to intersect mineralization associated with the Victoria mineralized zone.
The Victoria zone is discussed in more detail in Section 7.4.2.
Yessi vein
During an infill
drilling campaign conducted in August 2023, a new blind zone of alteration and brecciation was identified, resulting in the intersection
of mineralization approximately 200 m further to the east of the Victoria mineralized zone. Three holes initially intersected high-grade
mineralization and four additional holes have been completed to assist with interpreting its geometry and extent. Interpretative
work supported by additional drilling to better define the geometry and character of the Yessi vein, and its relationship to the regional
structural architecture was underway as at the effective date of this Report. Initial interpretative work suggests the Yessi vein forms
part of the wider San Jose scale reidal system and may represent an R’ structure.
In September 2018, Cuzcatlan signed a contract
with International Natural Resources Development to perform a district-scale remote-sensing based geological study. The study was performed
to potentially identify or extend the known hydrothermal alteration extents in the district using ASTER satellite imagery. The ASTER analysis
resulted in the mapping of significant zones of advanced argillic alteration which represent medium to long-term generative targets for
potential mineralized systems beyond the influence of the Trinidad deposit.
There is potential for additional mineralization
to be discovered in the San Jose Mine area. Cuzcatlan identified an exploration portfolio pyramid in order of available information:
| • | First pass generative: Prospects defined
using indirect tools such as the district ASTER analysis, including San Jose Sur, Los Vásquez, Ocotes Tepehuaje (Figure 9.2). Proposed
exploration would consist of surface mapping and sampling, dependent on the acquisition of surface access rights. |
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Technical Report |
| · | Second
pass generative: Prospects are based on areas with mining history, significant alteration footprints, or previous inconclusive studies.
The San Martin de los Cansecos area is representative of this category (Figure 9.2). |
| · | Opportunity:
Prospects that require the acquisition of surface access rights are assigned to an opportunity fund. These include the Guila prospect
area with the potential for discovery of new veins and mineralization associated with rhyolitic domes in the district (Figure 9.2).
This fund also includes exploration activities in the Taviche corridor. |
| · | Priority
Drilling: These targets are based close to the mine infrastructure with potential of economic mineralization. These targets are generated
from geological assessments considering structural and alteration interpretations as well as lithological features and extrapolation
of geochemical data from known Inferred Resource regions. The Yessi vein target is an example of this criterion having been prioritized
for further exploration. |
Figure
9.2 Map showing location of generative exploration programs
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Technical Report |
In the opinion of the QP:
| · | The mineralization style and setting of the San
Jose Mine area is sufficiently well understood to support Mineral Resource and Mineral Reserve estimation. |
| · | Exploration methods are consistent with industry
practices and are adequate to support continuing exploration and Mineral Resource estimation. |
| · | Exploration results support the current interpretation
of the geological setting and mineralization. |
| · | A number of prospect areas have been identified
that may result in discoveries of additional mineralization or extensions to known mineralized zones. |
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Technical Report |
As of June 30, 2023, the data cut-off date,
a total of 1,460 drill holes totaling 463,774.55 m have been successfully completed at the San Jose Mine (Table 10.1, Figure 10.1)
with the drilling being concentrated in the Trinidad deposit. Wide-spaced exploration drilling has also been completed in the San Ignacio
area along the southern extension of the structurally controlled mineralized corridor (south of 1846500N), and to the far north of the
Trinidad deposit beyond 1847800N, as well as in the Victoria mineralized zone.
Table 10.1
Drilling by company and period at the San Jose Mine
Company |
Area |
Year |
No. of Drillholes |
Meters |
Pan American |
San Ignacio |
2001 |
2 |
242.00 |
Trinidad |
2001 |
3 |
851.50 |
Continuum |
San Ignacio |
2004 |
2 |
506.85 |
Trinidad |
2004 |
11 |
3,612.15 |
2005 |
2 |
757.85 |
Taviche |
2004 |
2 |
779.30 |
2006 |
10 |
2,179.40 |
Cuzcatlan |
El Rancho |
2011 |
9 |
2,621.90 |
San Ignacio |
2006 |
13 |
3,790.30 |
2007 |
23 |
8,910.20 |
2011 |
17 |
8,307.25 |
2012 |
9 |
3,970.60 |
2018 |
4 |
2,613.75 |
2019 |
2 |
950.35 |
2021 |
5 |
1,855.95 |
Trinidad |
2006 |
25 |
8,392.10 |
2007 |
43 |
17,675.85 |
2008 |
108 |
31,504.00 |
2009 |
4 |
1,410.50 |
2012 |
15 |
8,574.30 |
2013 |
66 |
27,462.35 |
2014 |
90 |
35,955.65 |
2015 |
78 |
24,820.95 |
2016 |
87 |
25,030.95 |
2017 |
82 |
23,841.10 |
2018 |
95 |
31,905.30 |
2019 |
73 |
16,160.10 |
2020 |
100 |
16,615.30 |
2021 |
90 |
14,120.75 |
2022 |
133 |
30,663.50 |
2023 |
5 |
3,592.45 |
Taviche |
2011 |
10 |
2,552.95 |
El Pochotle |
2012 |
11 |
3,387.05 |
La Altona |
2012 |
3 |
1,040.35 |
La Noria |
2015 |
1 |
743.75 |
2016 |
9 |
5,414.95 |
2020 |
3 |
1,417.65 |
Maria Vein |
2017 |
3 |
1,672.05 |
Victoria |
2015 |
6 |
3,613.20 |
2016 |
9 |
5,588.25 |
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Technical Report |
Company |
Area |
Year |
No. of Drillholes |
Meters |
|
|
2017 |
23 |
11,737.45 |
2018 |
31 |
15,291.05 |
2019 |
7 |
3,657.25 |
2020 |
1 |
618.30 |
2021 |
9 |
3,546.00 |
2022 |
64 |
16,857.25 |
2023 |
55 |
14,320.50 |
Los Diaz |
2020 |
4 |
2,494.55 |
2021 |
3 |
2,142.60 |
Totals |
2001–2023* |
1,460 |
463,774.55 |
* As of June 30, 2023 – Database cut-off date for Mineral
Resource and Mineral Reserve estimation.
Drilling completed after June 30, 2023 has been reported in Section 10.3
for completeness.
The above does not include 59 drill holes totaling 7,060.85 m that
were aborted and redrilled due to poor ground conditions and five drill holes totaling 1,162.25 m that were drilled for services. |
Figure 10.1 Drill hole location map
for the San Jose Mine
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Of the areas drilled, sufficient continuity of
mineralization has only been encountered in the Trinidad deposit area and the Victoria mineralized zone to support the estimation of Mineral
Resources.
A total of 1,110 core holes totaling 330,951.55
m have been drilled in the Trinidad deposit area and 205 holes totaling 75,229.25 m in the Victoria mineralized zone (Figure 10.1). In
Trinidad, the majority of the holes have been drilled from east to west to crosscut the steeply east-dipping mineralized zone at high
angles, whereas in the Victoria mineralized zone, the holes have been drilled from west to east from underground to intersect the subvertical
Victoria main structure. Of the 1,460 holes, 465 have been drilled from the surface and the remainder from underground.
All of the drilling was conducted by core drilling
methods with the exception of 1,476 m of reverse circulation (RC) pre-collars in six of the 1,460 core drill holes.
The core drilling typically commences with HQ
(63.5 mm core diameter) core and continues to the maximum depth allowable based on the mechanical capabilities of the drill equipment.
Once this point is reached or poor ground conditions are encountered the hole is cased and further drilling undertaken with smaller diameter
drilling tools with the core diameter being reduced to NQ2 (50.6 mm) or NQ (47.6 mm) size to completion of the hole (Table 10.2). In the
Trinidad deposit, five of the drill holes were further reduced to BQ (36.4 mm) size to complete the drill holes to the target depths.
All the drilling completed has been carried out by contract drilling service companies. PQ (85 mm) size drill core is related to the drilling
of the first 100 to 200 m from surface, where rock can be brittle or highly weathered. Once rock conditions improve the hole is protected
with a casing allowing the reduction to HQ or NQ diameter.
Table 10.2 Drilling by core diameter
size
Meters
drilled by area |
Core
Size Diameter |
PQ |
HQ |
NQ2 |
NQ |
BQ |
RCD# (Precollar) |
TOTAL |
(85 mm) |
(63.5 mm) |
(50.6 mm) |
(47.6 mm) |
(36.4 mm) |
El Pochotle |
|
3,387.05 |
|
|
|
|
3,387.05 |
El Rancho |
|
2,621.90 |
|
|
|
|
2,621.90 |
La Altona |
|
941.5 |
|
98.85 |
|
|
1,040.35 |
La Noria |
544.9 |
4,751.60 |
|
2,231.25 |
48.6 |
|
7,576.35 |
Maria vein |
|
1,469.10 |
|
202.95 |
|
|
1,672.05 |
San Ignacio |
206.05 |
20,795.65 |
10.2 |
10,135.35 |
|
|
31,147.25 |
Trinidad* |
817.25 |
182,385.80 |
6,036.25 |
139,029.60 |
767.3 |
1,475.6 |
330,511.80 |
Taviche |
|
5,511.65 |
|
|
|
|
5,511.65 |
Victoria |
42.1 |
30,957.00 |
|
43,312.75 |
477.4 |
|
74,789.25 |
Los Diaz |
682.9 |
2,633.30 |
|
1,320.95 |
|
|
4,637.15 |
TOTAL |
2,293.20 |
255,454.55 |
6,046.45 |
196,331.70 |
1,293.30 |
1,475.60 |
462,894.80 |
*879.75 m of historical core has no core size recorded. |
#Reverse circulation drilling. |
| 10.2.1 | Pan American campaign (2001) |
Of the five drill holes drilled by Pan American
in 2001, three of the drill holes were located in the Trinidad deposit area and two were located along the southern extension of the vein
system in the San Ignacio area. Two of the three drill holes located in the vicinity of the Trinidad shaft intercepted strong silver and
gold. The two drill holes located in the San
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Ignacio area intercepted weak to moderate grade silver–gold mineralization over narrow
to moderate vein widths.
| 10.2.2 | Continuum campaigns (2004 to 2006) |
Between 2004 and 2006 Continuum drilled a total
of 27 surface core holes. Thirteen of the drill holes were located in the Trinidad deposit area, two were located in the San Ignacio area,
and 12 were in the Taviche area. Nine of the 13 drill holes completed in the Trinidad area intersected moderate to strong silver–gold
mineralization over significant widths. The two drill holes in the San Ignacio area and 12 holes in the Taviche area intercepted low-grade
silver–gold mineralization over narrow widths.
| 10.2.3 | Cuzcatlan campaigns (2006 to 2023) |
Drilling conducted in 2006
During 2006, Cuzcatlan completed the drilling
of 38 core holes, with 25 of the drill holes being located in the Trinidad deposit area and 13 in the San Ignacio area. The drilling in
the Trinidad deposit area confirmed the results of the prior drilling and expanded the mineralization along strike and to depth. Drilling
in the San Ignacio area identified significant zones of silver–gold mineralization over generally narrow vein widths.
Drilling conducted in 2007
During 2007, Cuzcatlan completed 66 core holes.
Forty-three of the drill holes were located in the Trinidad Deposit area and 23 drill holes in the San Ignacio area. Drilling in the Trinidad
deposit continued to confirm the potential and further expand the mineralization along strike to the south and at depth. Three-dimensional
modeling and evaluation of the drilling results in the Trinidad deposit indicated that additional infill drilling would be required in
order to potentially support conversion of Inferred Mineral Resources to the Indicated Mineral Resource classification.
Drilling conducted in 2008–2009
Based on the combined results of the drilling
completed in the Trinidad deposit through 2007 and on the results of deposit evaluation, an infill drill program was designed and carried
out to potentially support conversion of a majority of the Inferred Mineral Resources above the 1,300-meter elevation to Indicated Mineral
Resources. During 2008 and early 2009, Cuzcatlan completed a total of 112 drill holes with the majority of the drilling being directed
towards the upper portions of the Trinidad deposit. The results of the infill drilling confirmed the presence of high-grade silver–gold
mineralization in the Trinidad deposit and led to the development of a detailed geological and mineralization model of the deposit. All
work was supervised directly by Cuzcatlan and Fortuna. Drilling activities were carried out by contractors; Construccion, Arrendamiento
de Maquinaria y Minera, S.A. de C.V. and by Rodio Swissboring Mexico, S.A. de C.V.
Drilling conducted in 2011
During 2011, Cuzcatlan completed 17 core holes
to the south of the Trinidad deposit area in the San Ignacio area. While some of these drill holes encountered mineralized intervals,
it was recommended that additional drilling be conducted in this area in order to demonstrate mineralization continuity.
Cuzcatlan also completed 10 core holes at El Rancho
and 10 core holes at Taviche based on promising surface mapping. The drilling failed to identify significant mineralization.
Drilling conducted in 2012
During 2012, Cuzcatlan completed 16 drill core
holes in the northern part of the Trinidad deposit area as well as nine drill holes in the San Ignacio area. Drilling completed in the
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Trinidad deposit was successful in demonstrating the
extension of significant silver and gold mineralization to the north and to depth and resulted in the continuation of the drill
program into 2013. Underground drilling commenced at the end of 2012 with the completion of a single drill hole intersecting the
main Stockwork Zone.
Cuzcatlan also completed the drilling of several prospect areas including El Pochotle (11 core holes) and La
Altona (three core holes). Both programs failed to identify any significant intervals of mineralization.
Drilling
conducted in 2013–2014
During 2013
and 2014, Cuzcatlan focused on further exploring and defining the Trinidad deposit by completing 155 drill holes. Surface and underground
exploration drilling focused on expanding the extent of mineralization to the north. Underground infill drilling focused on potentially
upgrading Inferred Mineral Resources to higher confidence categories and refining geological interpretations in the main Stockwork Zone.
Drilling
conducted in 2015–2016
From January 2015 to the end of 2016, Cuzcatlan
completed 166 drill holes in the Trinidad deposit. Surface and underground exploration drilling focused on expanding the Trinidad deposit
extents. Underground infill drilling focused on providing support for upgrading Inferred Mineral Resources to higher confidence categories
and refining geological interpretations in the Stockwork Zone and in the north of the Trinidad deposit.
Cuzcatlan also began an exploration drill program
focusing on the Victoria mineralized zone to the east of the Trinidad deposit. Drilling of seven core in 2015 and nine core holes in 2016,
was conducted from underground chambers located near the Trinidad deposit. Mineralized intervals were encountered in the majority of the
drill holes indicating follow-up drilling was required to define the potential of this new vein system.
In late 2015 and in 2016, Cuzcatlan also tested
the La Noria prospect completing 10 core holes.
Drilling conducted in 2017-2018
From January 2017 to June 30, 2018,
Cuzcatlan completed 141 drill core holes in the Trinidad deposit area. Exploration continued to the far north of the deposit and at depth
below the currently defined Trinidad central area. Infill drilling focused on defining the mineralization in the Stockwork 2 and Stockwork
3 zones.
Drilling of the Victoria mineralized zone continued
with 36 core holes being drilled from underground and focused on expanding the preliminary defined area of mineralization and attempting
to establish geological and mineralized continuity between drill holes.
Additional prospects were also drilled on the
San Jose Project area during this period, including four core holes at San Ignacio and three core holes at the Maria vein. Silver–gold
mineralization at San Ignacio is related to narrow zones in the continuity of the stockwork at the south sector of the mine with irregular
distribution and variable results between the elevations 1,080 masl to 1,200 masl. Mineralization at Taviche and Maria is related to base
metals with silver anomalies in narrow and irregular veinlets and breccias.
Drilling conducted in 2019-2023
For the period from July 1, 2018, to December 31,
2023, Cuzcatlan drilled 651 core holes.
During the second half of 2018 to December 31,
2023 the drilling programs were focused on exploring the continuity of the mineralization in the far north of the deposit, testing the
continuity of the Trinidad system considering the influence of the plunge of the
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mineralization dipping to the north as well as the projection
of the silicified outcrop which is believed to be the convergence point of the Victoria mineralized zone and the Trinidad system. The
exploration in the north and central sectors of the Victoria mineralized zone continued with 177 core holes focused on testing the expansion
of the mineralization to the north and south.
During the second half of 2018, additional exploration
was conducted on the south deep sector of the Trinidad system to test the continuity of the mineralization in the southern extension of
the Stockwork structure.
During 2019, exploration drilling resulted in
the definition of a shallower northern extension of the mineralization on the periphery of the Trinidad system between the coordinates
1847200N and 1847400N and above 1,300 masl.
During 2020, data reviews and geophysical assessments
identified a potential south extension of the regional structure related to the projection of the Trinidad system merging with the Los
Diaz area. The area was tested by seven core holes.
During the 2023 infill drilling campaign, a new
blind zone of alteration and brecciation was intersected approximately 200 me further to the east of the Victoria mineralized zone and
subsequently named the Yessi vein. Three core holes initially defined high-grade mineralization and four additional holes were drilled
to assist with interpreting its geometry and extent.
| 10.3 | Drilling conducted post database cut-off date |
As of the effective date of this Report an additional
37 exploration core drill holes totaling 10,194.1 m were completed after the June 30, 2023, database cut-off date. All drilling was
carried out from underground drill stations with the exception of three holes. Assay results for intercepts of interest are summarized
in Table 10.3. Thirteen of the exploration drill holes targeted the Trinidad deposit, 17 targeted the Victoria mineralized zone, and seven
targeted the Yessi vein. All drill holes are located beyond the current Mineral Resource estimate boundary.
Table 10.3 Drill intervals in the
Trinidad deposit and Victoria mineralized zone encountered post data cut-off date
Hole ID |
Easting |
Northing |
Elevation |
Azimuth
(°)* |
Dip
(°)* |
From
(m) |
To
(m) |
Drilled Interval
(m) |
ETW**
(m) |
Ag
(g/t) |
Au
(g/t) |
SJOM-1379 |
745296.9 |
1847651.9 |
1238.4 |
70.9 |
27.0 |
84.00 |
93.73 |
9.73 |
9.50 |
125 |
0.80 |
SJOM-1380 |
745296.5 |
1847652.2 |
1235.8 |
52.5 |
-37.7 |
160.45 |
164.45 |
4.00 |
2.20 |
138 |
1.10 |
SJOM-1381 |
745192.5 |
1847930.0 |
1235.3 |
81.1 |
-37.6 |
167.00 |
174.82 |
7.82 |
3.80 |
102 |
0.80 |
SJOM-1383 |
745192.7 |
1847929.5 |
1235.3 |
81.1 |
-37.6 |
170.55 |
178.24 |
7.69 |
3.80 |
31 |
0.28 |
SJOM-1384 |
745296.5 |
1847651.9 |
1235.8 |
54.7 |
-42.3 |
210.00 |
215.00 |
5.00 |
2.90 |
11 |
0.10 |
SJOM-1385 |
745192.3 |
1847931.8 |
1235.4 |
56.7 |
-32.4 |
130.18 |
135.47 |
5.29 |
3.10 |
162 |
1.13 |
SJOM-1386 |
745192.3 |
1847931.5 |
1235.2 |
51.6 |
-26.8 |
118.15 |
122.65 |
4.50 |
3.02 |
60 |
0.43 |
SJOM-1387 |
745297.9 |
1847649.5 |
1236.5 |
100.6 |
-12.1 |
233.40 |
325.20 |
91.8 |
18.00 |
161 |
1.30 |
SJOM-1389 |
745192.4 |
1847931.5 |
1235.2 |
54.4 |
-39.0 |
152.26 |
158.17 |
5.91 |
2.98 |
109 |
1.00 |
SJOM-1390 |
744959.5 |
1847791.0 |
846.9 |
74.7 |
-32.8 |
no significant intervals |
SJOM-1391 |
745297.9 |
1847649.5 |
1236.2 |
100.9 |
-20.2 |
155.45 |
162.40 |
6.95 |
4.18 |
41 |
0.17 |
337.15 |
345.00 |
7.85 |
1.20 |
386 |
3.13 |
SJOM-1392 |
745192.2 |
1847932.5 |
1235.3 |
43.8 |
-31.2 |
135.62 |
142.40 |
6.78 |
3.85 |
36 |
0.32 |
SJOM-1393 |
744959.4 |
1847790.5 |
846.9 |
89.3 |
-32.5 |
no significant intervals |
SJOM-1395 |
745191.4 |
1847933.0 |
1235.5 |
37.0 |
-29.7 |
223.22 |
226.50 |
3.28 |
2.17 |
34 |
0.29 |
SJOM-1396 |
745298.0 |
1847649.4 |
1236.8 |
101.9 |
-2.6 |
272.12 |
276.00 |
3.88 |
1.00 |
64 |
0.49 |
SJOM-1397 |
744959.5 |
1847791.1 |
846.9 |
66.8 |
-34.5 |
149.00 |
151.80 |
2.8 |
3.00 |
0 |
2.10 |
SJOM-1398 |
745192.7 |
1847929.9 |
1236.2 |
91.5 |
-0.9 |
No significant intervals |
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Hole ID |
Easting |
Northing |
Elevation |
Azimuth
(°)* |
Dip
(°)* |
From
(m) |
To
(m) |
Drilled Interval
(m) |
ETW**
(m) |
Ag
(g/t) |
Au
(g/t) |
SJOM-1399 |
745298.0 |
1847649.4 |
1237.4 |
104.0 |
8.4 |
133.95 |
140.65 |
6.7 |
5.01 |
64 |
0.63 |
SJOM-1400 |
745192.7 |
1847929.9 |
1235.3 |
88.8 |
-38.5 |
No significant intervals |
SJOM-1401 |
745192.6 |
1847930.1 |
1235.3 |
87.8 |
-40.5 |
202.45 |
211.11 |
8.66 |
3.59 |
9 |
0.11 |
SJOM-1402 |
745010.6 |
1847738.4 |
834.2 |
46.1 |
8.0 |
97.65 |
101.45 |
3.80 |
3.50 |
160 |
0.88 |
SJOM-1403 |
745192.4 |
1847930.5 |
1236.1 |
73.4 |
-4.4 |
93.05 |
95.35 |
2.30 |
2.05 |
10 |
0.15 |
SJOM-1405 |
745192.3 |
1847930.6 |
1235.4 |
68.9 |
-45.0 |
no significant intervals, hole abandoned |
SJOM-1406 |
745011.8 |
1847737.8 |
833.8 |
72.4 |
-5.8 |
116.35 |
119.50 |
3.15 |
3.06 |
2,628 |
13.12 |
SJOM-1407 |
745010.7 |
1847739.5 |
833.9 |
26.3 |
-3.7 |
No significant intervals |
SJOM-1409 |
745192.4 |
1847931.2 |
1235.0 |
60.1 |
-45.0 |
304.60 |
312.30 |
7.70 |
4.25 |
83 |
0.54 |
SJOM-1410 |
745011.7 |
1847738.1 |
834.3 |
63.6 |
7.3 |
97.90 |
104.95 |
7.05 |
7.01 |
362 |
2.13 |
SJOM-1411 |
745011.8 |
1847737.8 |
834.2 |
86.5 |
4.8 |
36.30 |
39.15 |
2.85 |
2.83 |
11 |
0.05 |
SJOM-1412 |
745192.3 |
1847932.4 |
1235.8 |
47.2 |
-13.9 |
No significant intervals |
SJOM-1413 |
745011.8 |
1847737.6 |
833.7 |
88.8 |
-17.5 |
123.90 |
124.25 |
0.35 |
0.35 |
184 |
1.06 |
SJOM-1414 |
745192.0 |
1847932.6 |
1235.0 |
44.2 |
-45.1 |
216.00 |
217.46 |
1.46 |
|
114 |
1.03 |
SJOM-1382 |
744901.9 |
1849292.9 |
1252.9 |
74.3 |
-5.8 |
No significant intervals |
SJO-1388 |
745794.9 |
1847115.8 |
1545.2 |
249.9 |
-44.8 |
No significant intervals |
SJO-1394 |
745990.5 |
1846953.0 |
1549.1 |
230.7 |
-55.6 |
No significant intervals |
SJOM-1404 |
745298.0 |
1847649.2 |
1236.6 |
108.7 |
-8.0 |
286.20 |
286.70 |
0.50 |
0.10 |
109 |
1.00 |
308.85 |
309.60 |
0.75 |
0.15 |
138 |
1.11 |
325.95 |
326.60 |
0.65 |
0.15 |
68 |
0.34 |
372.25 |
372.95 |
0.70 |
0.15 |
69 |
0.46 |
386.20 |
386.90 |
0.70 |
0.15 |
189 |
0.88 |
390.10 |
391.00 |
0.90 |
0.20 |
41 |
0.43 |
SJOM-1408 |
745297.895 |
1847649.45 |
1236.14 |
106.4844 |
-22.5 |
351.15 |
352.00 |
0.85 |
0.20 |
46 |
0.50 |
352.75 |
354.00 |
1.25 |
0.30 |
43 |
0.57 |
355.35 |
356.20 |
0.85 |
0.21 |
68 |
0.78 |
359.20 |
364.45 |
5.25 |
1.30 |
57 |
0.61 |
369.10 |
370.10 |
1.00 |
0.25 |
59 |
0.39 |
370.85 |
371.35 |
0.50 |
0.13 |
204 |
1.71 |
372.75 |
373.85 |
1.10 |
0.30 |
77 |
0.60 |
376.10 |
377.75 |
1.65 |
0.40 |
56 |
0.54 |
379.40 |
381.30 |
1.90 |
0.50 |
99 |
0.86 |
385.25 |
386.70 |
1.45 |
0.40 |
48 |
0.39 |
390.50 |
402.20 |
11.70 |
2.95 |
131 |
1.11 |
406.65 |
407.95 |
1.30 |
0.35 |
140 |
1.24 |
413.30 |
414.25 |
0.95 |
0.24 |
44 |
0.55 |
415.75 |
420.60 |
4.85 |
1.20 |
142 |
1.13 |
424.50 |
430.00 |
5.50 |
1.40 |
140 |
1.05 |
439.50 |
441.55 |
2.05 |
0.50 |
102 |
1.07 |
444.45 |
446.00 |
1.55 |
0.40 |
62 |
0.67 |
451.55 |
452.90 |
1.35 |
0.35 |
51 |
0.52 |
471.25 |
472.30 |
1.05 |
0.25 |
276 |
2.40 |
473.35 |
475.00 |
1.65 |
0.40 |
60 |
0.49 |
SJOM-1366A |
745297 |
1847650 |
1236 |
95.09 |
-27.91 |
324.70 |
325.25 |
0.55 |
0.15 |
63 |
0.47 |
326.50 |
330.00 |
3.50 |
0.75 |
2 |
0.59 |
340.60 |
341.80 |
1.20 |
0.25 |
43 |
0.36 |
365.00 |
368.75 |
3.75 |
0.80 |
64 |
0.58 |
381.50 |
382.75 |
1.25 |
0.30 |
139 |
0.03 |
446.30 |
448.75 |
2.45 |
0.50 |
41 |
0.40 |
459.65 |
460.85 |
1.20 |
0.30 |
64 |
0.58 |
461.75 |
462.25 |
0.50 |
0.10 |
58 |
0.52 |
464.10 |
465.70 |
1.60 |
0.35 |
195 |
1.58 |
486.30 |
487.20 |
0.90 |
0.60 |
223 |
1.70 |
539.70 |
540.05 |
0.35 |
0.10 |
40 |
0.50 |
542.55 |
543.00 |
0.45 |
0.10 |
123 |
1.13 |
557.00 |
557.35 |
0.35 |
0.10 |
123 |
1.57 |
568.00 |
568.70 |
0.70 |
0.15 |
50 |
0.61 |
573.45 |
575.40 |
1.95 |
0.40 |
90 |
0.83 |
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Technical Report |
Hole ID |
Easting |
Northing |
Elevation |
Azimuth
(°)* |
Dip
(°)* |
From
(m) |
To
(m) |
Drilled Interval
(m) |
ETW**
(m) |
Ag
(g/t) |
Au
(g/t) |
|
|
|
|
|
|
582.85 |
584.35 |
1.50 |
0.30 |
83 |
0.82 |
586.30 |
586.85 |
0.55 |
0.10 |
224 |
1.52 |
587.80 |
589.10 |
1.30 |
0.30 |
255 |
1.85 |
590.25 |
592.50 |
2.25 |
0.50 |
67 |
0.72 |
595.80 |
596.10 |
0.30 |
0.05 |
157 |
1.71 |
596.50 |
597.60 |
1.10 |
0.25 |
62 |
0.70 |
599.35 |
601.90 |
2.55 |
0.55 |
102 |
0.75 |
602.80 |
603.25 |
0.45 |
0.10 |
62 |
0.56 |
606.55 |
607.30 |
0.75 |
0.15 |
58 |
0.49 |
607.65 |
608.10 |
0.45 |
0.10 |
199 |
1.44 |
609.00 |
609.75 |
0.75 |
0.15 |
193 |
1.27 |
617.10 |
617.55 |
0.45 |
0.10 |
235 |
2.15 |
618.30 |
618.70 |
0.40 |
0.10 |
57 |
0.51 |
621.05 |
621.40 |
0.35 |
0.10 |
132 |
1.34 |
623.80 |
625.00 |
1.20 |
0.65 |
99 |
0.83 |
626.15 |
626.60 |
0.45 |
0.10 |
45 |
0.36 |
627.15 |
627.60 |
0.45 |
0.10 |
64 |
0.66 |
636.40 |
640.55 |
4.15 |
0.90 |
166 |
1.24 |
641.45 |
643.45 |
2.00 |
0.40 |
216 |
1.65 |
649.15 |
649.55 |
0.40 |
0.10 |
110 |
1.14 |
685.35 |
685.70 |
0.35 |
0.24 |
221 |
1.88 |
*Azimuth and dip values taken at collar location
**ETW = estimated true width |
| 10.4 | Geological and geotechnical logging procedures |
Cuzcatlan has a standardized rock unit classification
scheme, logging procedures, and log sheet structure that were used throughout the logging of all Cuzcatlan drill holes up until 2017.
The system used paper forms, and the data was subsequently entered into an Excel template. Geological logging took place after the core
was sampled, to take advantage of the flat sawed surface. Rock types and structure were recorded with alphanumeric codes, whereas alteration,
veinlets, minerals, and oxidation were recorded by a 1 to 3 scale (weak, moderate, strong). A core library was developed to illustrate
all rock and alteration types.
In 2018 all logging became digital, being incorporated
daily into the Maxwell Datashed database system. Data were recorded initially with Excel templates, and later with the Maxwell LogChief
application using essentially the same structure. Both input methods used pick-lists and data validation rules to ensure consistency
between loggers. Separate sheets were designed to capture metadata, lithology, alteration, minerals (sulfides, oxides, and limonite),
structure (contacts, fractures, veins, and faults with attitudes to core axis). Intensity of alteration phases was recorded using a numeric
1 to 4 scale (weak, moderate, strong, complete).
Geotechnical logging consists of the collection
of specified data fields including: recovery percentage and rock quality designation (RQD) length. Joint filling and joint weathering
are described as part of geological logging. A tablet-based data entry program was developed by Cuzcatlan using the Maxwell LogChief software.
Data checks are implemented into this program to prevent erroneous data entry.
Once geological
and geotechnical logging were complete and intervals were marked on the core for geochemical analysis an evaluation of alteration minerals
was conducted using Terraspec Halo equipment. The process involved taking a reading from the core every 5 m using a calibrated hand-held
device, or when an interval had been marked for
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geochemical sampling. Once all the readings for a drill hole were obtained, the information
was loaded into Datashed, and spectral log reports generated for each drill hole.
Core recovery for the drilling completed to-date
in the Trinidad deposit and Victoria mineralized zone where Mineral Resources have been estimated averages 98 % (Figure 10.3). Core recovery
within the mineralized zones is generally high due to the association of silicification and carbonatization with the mineralizing processes.
Figure 10.2
Graph of core recovery of Trinidad Deposit and Victoria mineralized zone
Figure prepared by Cuzcatlan, 2023 |
To-date, drilling has been conducted at the Trinidad
deposit over a strike length of approximately 3,000 m and to depths exceeding 1,000 m from surface, identifying mineralization over a
strike length of 1,400 m and 800 m down dip. Exploration drilling has generally increased in depth to the north.
Drilling of the Victoria mineralized zone has
been conducted over a strike length of approximately 2,300 m and covers a vertical extent of approximately 700 m, with upper holes intersecting
the structure at least 250 m below the surface.
The extent of drilling of the San Ignacio area
continues directly to the south of the Trinidad deposit and has been conducted over a strike length of approximately 1,000 m and to depths
of up to 500 m from surface.
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| 10.7 | Drill hole collar surveys |
Surface drill hole collars were surveyed using
differential global positioning system (GPS) and total station survey methods. Concrete monuments are constructed at each collar location
recording the drill hole name, azimuth, inclination and total depth. At locations where the drill hole collar is located in a cultivated
field, the collar monument is constructed approximately 50 cm below the actual surface.
Underground drill hole collars were surveyed using
total station survey methods. Concrete monuments similar to those used for surface collars are constructed to mark the location with the
drill hole name, azimuth, inclination and total depth recorded.
Down-hole surveys were completed for 1,443 of
the 1,460 drill holes completed as of the database cut-off date. For the 17 holes where downhole surveys are not recorded, all of which
were drilled prior to 2007, only three are within the Trinidad deposit area. The azimuth and dip orientation of these holes was recorded
at the collar to account for drilling direction. The absence of downhole surveys in three of the 1,315 holes drilled at Trinidad and Victoria
is not regarded as material to the Mineral Resource estimate.
Downhole surveys are typically completed at 50
m intervals although recent drill holes include downhole surveys at 10 m intervals until reaching 50 m depth and then at 50 m intervals
thereafter. All downhole surveys have been carried out by the drilling contractor using Reflex electronic downhole survey tools.
Representative drill sections displaying the mineralized
interpretation of the Trinidad deposit are displayed in Figures 10.3 to 10.6. A plan view showing the location of the sections is provided
in Figure 7.6.
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Figure 10.3
Section displaying mineralization along 1846925N
Silver equivalent calculated using a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and 91 % for Au
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Figure 10.4 Section displaying
mineralization along 1846975N
Silver equivalent calculated using a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and 91 % for Au
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Figure 10.5
Section displaying mineralization along 1847500N
Silver equivalent calculated using a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and 91 % for Au
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Figure 10.6
Section displaying mineralization along 1848200N
Silver equivalent calculated using a gold to silver ratio of 76:1 based on metal prices of US$ 1,600/oz Au and US$ 21/oz Ag and metallurgical recoveries of 92 % for Ag and 91 % for Au
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| 10.10 | Sample length versus true thickness |
The relationship between the sample intercept
lengths and the true width of the mineralization varies in relation to the intersect angle between the steeply-dipping zone of mineralized
veins and the inclined nature of the diamond core holes. Calculated estimated true widths (ETWs) are always reported together with actual
sample lengths by taking into account the angle of intersection between drill hole and the mineralized structure. Exaggeration of the
true width of the mineralization does not occur during modeling as the actual vein contacts are modeled in three-dimensional space to
create vein solids that are subsequently used to constrain estimation of Mineral Resources.
| 10.11 | Summary of drill intercepts |
Table 10.4 provides a list of typical drill hole
intercepts encountered at the San Jose Mine. It should be noted that the intervals listed are a subset for reference purposes only and
do not represent the total mineralized intervals encountered from the 1,460 drill holes drilled at the San Jose Mine. The intervals in
Table 10.4 are summarized from press releases detailing the most relevant exploration results reported by Fortuna since 2008.
Table 10.4
Example of typical drill results at the Trinidad Deposit and Victoria mineralized zone
Hole ID |
Easting |
Northing |
Elevation |
Azimuth (°)* |
Dip
(°)* |
From (m) |
To (m) |
Int.
(m) |
ETW**
(m) |
Ag
(g/t) |
Au
(g/t) |
SJO-119 |
745300 |
1846875 |
1546 |
270 |
-60 |
227 |
235.4 |
8.4 |
4.9 |
229 |
2.03 |
SJO-211 |
745204 |
1847250 |
1538 |
270 |
-50 |
210.75 |
212.5 |
1.75 |
1.2 |
142 |
1.4 |
218.4 |
219.4 |
1 |
0.7 |
184 |
0.81 |
SJO-261 |
745331 |
1847232 |
1539 |
290 |
-65 |
510.45 |
528.65 |
18.2 |
10.7 |
241 |
1.57 |
549.55 |
553.7 |
4.15 |
2.4 |
1,370 |
7.89 |
SJO-288 |
745330 |
1847261 |
1539 |
303 |
-64 |
551.85 |
591.1 |
39.25 |
19.3 |
736 |
4.76 |
596.7 |
602.8 |
6.1 |
3 |
529 |
4.69 |
SJO-295 |
745329 |
1847262 |
1539 |
303 |
-58 |
515 |
523.8 |
8.8 |
5.9 |
1,240 |
6.94 |
533.2 |
544 |
10.8 |
7.2 |
731 |
3.84 |
SJOM-335 |
745243 |
1847557 |
1312 |
296 |
-72 |
419 |
425.3 |
6.3 |
3.7 |
3,511 |
15.04 |
including |
420.05 |
421.7 |
1.65 |
1 |
12,249 |
51.89 |
|
439.2 |
454.7 |
15.5 |
9.1 |
474 |
2.54 |
|
495.5 |
498 |
2.5 |
1.5 |
151 |
0.76 |
SJOM-390 |
745244 |
1847558 |
1312 |
304 |
-56 |
397.7 |
410.15 |
12.45 |
6.3 |
128 |
0.65 |
413.85 |
421.9 |
8.05 |
4 |
636 |
2.93 |
SJOM-400 |
745205 |
1847509 |
1311 |
298 |
-28 |
297.8 |
299.1 |
1.3 |
1 |
78 |
0.41 |
SJOM-406 |
745206 |
1847507 |
1313 |
270 |
0 |
No significant mineralized intervals |
SJOM-513 |
745082 |
1846785 |
1076 |
42 |
-35 |
304.85 |
305.5 |
0.65 |
0.5 |
462 |
1.95 |
307.85 |
308.15 |
0.3 |
0.2 |
188 |
1.02 |
SJOM-591# |
745033 |
1847800 |
1226 |
106 |
-14 |
426.8 |
434.5 |
7.7 |
4.1 |
247 |
1.81 |
including |
428 |
429.1 |
1.1 |
0.6 |
373 |
2.31 |
|
433.2 |
433.5 |
0.3 |
0.2 |
2,860 |
22.8 |
SJOM-649# |
745018 |
1848185 |
1228 |
85 |
-37 |
350 |
396 |
46 |
21 |
153 |
0.88 |
including |
383 |
390.4 |
7.4 |
3.6 |
281 |
1.24 |
|
394.5 |
396 |
1.5 |
0.7 |
918 |
6.29 |
|
409.5 |
414.3 |
4.8 |
2.2 |
230 |
1.45 |
SJOM-684# |
745018 |
1848184 |
1228 |
73 |
-38 |
194.6 |
202.2 |
7.6 |
3.7 |
1,106 |
6.34 |
SJO-1027# |
745889 |
1847614 |
1537 |
264 |
-75 |
652.70 |
655.55 |
2.85 |
2.2 |
51 |
0.83 |
SJOM-1036# |
745299 |
1847599 |
1316 |
110 |
5 |
163.00 |
164.60 |
1.60 |
1.0 |
47 |
0.58 |
194.30 |
195.50 |
1.20 |
0.8 |
104 |
0.89 |
SJOM-1047# |
745022 |
1848004 |
1228 |
97 |
27 |
217.00 |
217.50 |
0.50 |
0.4 |
228 |
1.08 |
230.40 |
232.10 |
1.70 |
1.5 |
163 |
1.77 |
SJO-1053# |
745902 |
1847352 |
1544 |
268 |
-45 |
630.20 |
634.30 |
4.10 |
1.5 |
290 |
2.00 |
including |
631.50 |
633.20 |
1.70 |
0.6 |
691 |
4.78 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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Hole ID |
Easting |
Northing |
Elevation |
Azimuth (°)* |
Dip
(°)* |
From (m) |
To (m) |
Int.
(m) |
ETW**
(m) |
Ag
(g/t) |
Au
(g/t) |
SJOM-1065 |
745018 |
1848004 |
1226 |
281 |
-62 |
112.70 |
113.30 |
0.60 |
0.3 |
50 |
0.50 |
|
118.40 |
120.40 |
2.00 |
1.0 |
136 |
1.38 |
|
237.45 |
237.75 |
0.30 |
0.2 |
39 |
0.41 |
|
271.30 |
276.75 |
5.45 |
2.8 |
98 |
0.49 |
including |
272.35 |
275.00 |
2.65 |
1.4 |
146 |
0.72 |
SJOM-1070A |
745016 |
1848008 |
1227 |
296 |
-27 |
153.60 |
160.55 |
6.95 |
4.0 |
77 |
0.38 |
including |
153.60 |
154.80 |
1.20 |
0.7 |
248 |
1.06 |
|
228.40 |
230.50 |
2.10 |
1.2 |
243 |
0.82 |
SJOM-1088 |
745017 |
1848007 |
1226 |
287 |
-39 |
148.00 |
148.75 |
0.75 |
0.6 |
72 |
0.02 |
155.70 |
156.35 |
0.65 |
0.5 |
58 |
0.45 |
159.90 |
161.05 |
1.15 |
0.9 |
43 |
0.39 |
162.50 |
168.40 |
5.90 |
4.6 |
245 |
1.41 |
251.10 |
252.40 |
1.30 |
1.0 |
127 |
0.80 |
SJOM-1091 |
744978 |
1848186 |
1228 |
276 |
-32 |
168.20 |
171.30 |
3.10 |
1.7 |
506 |
261 |
172.90 |
173.40 |
0.50 |
0.3 |
146 |
0.96 |
174.65 |
175.10 |
0.45 |
0.2 |
275 |
1.30 |
225.95 |
226.90 |
0.95 |
0.5 |
44 |
0.35 |
SJO-1093 |
745225 |
1846390 |
1573 |
273 |
-64 |
19.15 |
21.75 |
2.60 |
1.0 |
101 |
1.30 |
SJO-1096 |
745383 |
1845880 |
1574 |
269 |
-61 |
224.05 |
226.65 |
2.60 |
1.8 |
178 |
1.21 |
Collar coordinates rounded to nearest meter |
*Azimuth and dip values taken at collar location |
**ETW = Estimated True Width |
#Holes targeting the Victoria mineralized zone |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 10.12 | Comment on Section 10 |
The QP has the following observations and conclusions
regarding drilling conducted at the Project since 2001:
| · | Data were collected using industry standard practices. |
| · | Drill orientations are appropriate to the orientation
of the mineralization for the bulk of the area where Mineral Resources have been estimated (see Section 7.5 and Section 10.9
for representative cross-sections showing geology and mineralization, respectively). |
| · | Core logging meets industry standards for exploration
of epithermal-style deposits. Geotechnical logging is sufficient to support Mineral Resource estimation. |
| · | Collar surveys have been performed using industry-standard
instrumentation. |
| · | Downhole surveys performed during the drill programs
have been performed using industry-standard instrumentation. |
| · | Drilling information is sufficient to support Mineral Reserve and Mineral
Resource estimates. |
There are no drilling, sampling or recovery factors
that could materially impact the accuracy and reliability of the results known to the QP that are not discussed in the Report.
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| 11 | Sample Preparation, Analyses, and Security |
All samples are collected by geological staff
of Cuzcatlan with sample preparation and analysis being conducted at the Cuzcatlan on-site laboratory (Cuzcatlan Laboratory; channel samples
taken after February 2012 and infill and exploration drill core after April 23, 2018, and July 20, 2020, respectively).
Prior to the Cuzcatlan Laboratory achieving analytical accreditations, drill core was transported to the ALS Global preparation facility
in Guadalajara before being sent for analysis at their laboratory in Vancouver (all exploration drill core, channel samples taken prior
to February 2012, and infill drill core and exploration drill core prior to April 23, 2018, and March 5, 2020, respectively).
The Cuzcatlan Laboratory was awarded ISO certification as detailed in Section 11.3 on March 3, 2018. Pulp splits and preparation
duplicates, along with reference standards and blanks are routinely sent to the ISO-certified ALS Global preparation and analytical facilities
in Guadalajara and Vancouver respectively, in order to monitor the performance of the Cuzcatlan Laboratory.
| 11.1 | Sample preparation prior to dispatch of samples |
| 11.1.1 | Channel chip sampling |
Channel chip samples are generally collected from
the face of newly-exposed underground workings. The entire process is carried out under the mine geology department’s supervision.
The location of each channel sample is determined
using a compass and tape measure relative to a survey reference point determined at approximately 9 m intervals using total station equipment.
Samplers measure the azimuth and distance from the underground survey reference point to the location of the channel. The channel distance
information is recorded and used in conjunction with underground surveys so as to determine the starting coordinates of the channel. Each
channel is not individually surveyed, and the present methodology means the further the channel is from the survey reference point the
greater the potential for spatial error.
Sampling is carried out at 3 m intervals
within the drifts and stopes of all veins. The channel’s length and orientation are identified using paint in the underground working
and by painting the channel number on the footwall. The channel is approximately 20 cm wide and approximately 1 to 2 cm deep,
with each individual sample preferably being no smaller than 0.4 m and no longer than 1.5 m.
The area to be sampled is washed down to provide
a clean view of the vein. The channel is sampled by taking a succession of chips in sequence from the hanging wall to the footwall perpendicular
to the vein based on geology and mineralization.
Samples, comprised of fragments, chips and mineral
dust, are extracted using a chisel and hammer, along the channel’s length on a representative basis. For veins with narrow or reduced
thickness (<0.20 m), the channel depth is increased thus allowing the minimum sample mass (5 kg) to be collected.
Sample collection is normally performed by two
samplers, one using the hammer and chisel, and the other holding the receptacle (cradle), to collect rock and ore fragments. The cradle
consists of a sack, with the mouth kept open by a wire ring. Fragments greater than 6 cm in diameter are not accepted.
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The obtained sample
is deposited in a plastic sample bag with a sampling card and the assigned sample ID. The sampling equipment is then washed prior
to the collection of the next sample. Once all the samples in the channel have been collected the sample bags are transported to the surface
and sorted with quality control samples being inserted at industry standard insertion rates prior to delivery to the Cuzcatlan Laboratory.
Drill core is laid out for sampling and logging
at the core logging facility at the camp. Sample intervals are marked on the core and depths recorded on the appropriate box.
A geologist is responsible for determining and
marking the drill core intervals to be sampled, selecting them based on geological and structural logging. The sample length must not
exceed 2 m or be less than 20 cm.
Splitting of the core is performed by diamond
saw. The geologist carefully determines the line of cutting, in such a way that both halves of the core are representative. The core cutting
process is performed in a separate building adjacent to the core logging facilities. Water used to cool the saw is not re-circulated but
stored in a tank to allow any fines to settle before final disposal.
Once the core has been split, half the sample
is placed in a sample bag. A sampling card with the appropriate information is inserted with the core.
| 11.1.3 | Bulk density determination |
Bulk density samples have been primarily sourced
from drill core (5,403 measurements as of June 30, 2023) with a limited number being sampled from underground workings.
Bulk density measurements are performed at the
ALS Global Laboratory in Vancouver using the OA-GRA08 methodology. This test consists of coating the core sample in paraffin wax, measuring
the sample weight in air then suspending the sample in water and measuring the weight again. The bulk density is calculated using the
following equation:
Where
A = weight of sample in air
B = weight of waxed sample in air
C = weight of waxed sample suspended
in water
D = density of wax
Results of this analysis are included in Section 14.8
of this Report.
| 11.2 | Dispatch of samples, sample preparation, assaying and analytical procedures |
Following the sawing of drill core or the collection
of chip fragments underground (described above) samples were placed in polyethylene sample bags with a sample tag detailing a unique sample
identifier. The same sample identifier is marked on the outside
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of the bag and it is sealed with a cable tie. Secured sample bags are
then placed in rice sacks. Samples are delivered each day to the Cuzcatlan Laboratory for preparation and analysis.
Prior to the certification of the Cuzcatlan Laboratory,
samples of drill core were placed in rice sacks labeled with the company name, number of samples contained in the sack and the sample
number sequence. The rice sacks with the samples were then sealed with double cable ties and stored in a secure, dry and clean location.
The rice sacks were subsequently transported by authorized company personnel to commercial freight shipment offices in Oaxaca for air
transport to the ALS Global sample preparation facility in Guadalajara, Jalisco, Mexico.
Cuzcatlan Laboratory
Upon receipt of a sample batch the laboratory
staff immediately verifies that sample bags are sealed and undamaged. Sample numbers and IDs are checked to ensure they match that as
detailed in the submittal form provided by the geology department. If any damaged, missing, or extra samples are detected, the sample
batch is rejected, and the geology department is contacted immediately to investigate and resolve the discrepancy. If the sample batch
is accepted the samples are sequentially coded and registered as received.
Accepted samples are then transferred to individual
stainless-steel trays that have a maximum capacity of 7 kg, with their corresponding sample IDs for drying. If the sample is excessively
wet a little water is used to clean out the inside of the sample bag and ensure all fines are collected in the metal trays. The trays
are placed on a trolley then placed into an electric furnace oven for 2 to 4 hours at a temperature of 100 to 118°C until the sample
weight is constant.
Once samples have been dried, they are transferred
to a separate ventilated room for crushing. The operator checks the samples received match those on the submittal form before each sample
is fed into a terminator crusher in turn to reduce the original particle size so that 75 % passes a 10-mesh sieve size (2 mm). The sample
may have to be put through the crusher twice if the required particle size is not achieved on the first pass. The crushing equipment is
cleaned using compressed air and a barren quartz flush after each sample.
Once the sample has been crushed it is homogenized
and reduced in size to approximately 1,000 g using a single-tier Jones riffle splitter. The reduced sample is returned to the sampling
tray for pulverizing whereas the coarse reject material is returned to a labeled sample bag and temporarily placed in a separate storage
room for transferal to the long-term storage facilities.
Crushed samples are pulverized using a Rocklab
standard LM2 disc mill so that 85 % of particles pass a 200-mesh sieve size. The pulverized sample is then homogenized by placing it in
the center of a 40 cm x 50 cm rubber mat and lifting opposite corners five times each. The pulp sample is carefully placed in an envelope
along with the sample ID label. Envelopes are taken to the balance room where they are checked to ensure the samples registered as having
been received and processed match those provided in the envelopes.
ALS Global Laboratory
All exploration core samples were sent to the
ALS Global sample preparation facility in Guadalajara, Mexico until March 5, 2020, after which they were sent to the certified Cuzcatlan
Laboratory starting on July 20, 2013, when the next drill program commenced.
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Upon arrival, a notification of sample reception was
transmitted to Cuzcatlan, and the samples entered into the laboratory sample management system. Following drying, the samples were weighed,
and the entire sample crushed to a minimum of 70 % passing a 10-mesh sieve size. The crushed sample was then reduced in size by passing
the entire sample through a riffle splitter until a 250 g split was obtained. The 250 g split was then pulverized to a minimum
of 85 % passing a 200-mesh sieve size. The pulverized samples were subsequently grouped by sample lot and shipped by commercial air freight
to ALS Global’s analytical facility in Vancouver, British Columbia for analysis.
Cuzcatlan Laboratory
Upon receipt of samples in the analytical laboratory,
all pulps are re-checked to ensure they match the list in the submittal form. Two samples from the pulp envelope are then taken. One sample
is analyzed using atomic absorption (AA) spectroscopy and the other by fire assay (FA) with gravimetric finish. Atomic absorption results
are recorded when silver grades are less than 500 g/t or when gold grades are less than 6.5 g/t, otherwise the gravimetric results are
recorded.
For the AA finish, 2 g of the pulp is weighed
and added to a beaker, along with 40 ml of hydrochloric acid, 10 ml of nitric acid, and 10 ml of perchloric acid and heated
gently at 90–100 °C until all the sample is digested. It is then cooled before the volume is increased with distilled water
to approximately 200 ml prior to analysis by atomic absorption. Two machines are used, one calibrated for gold and one for silver.
The above process is equivalent to the ALS Global
OG62, four acid digestion with atomic absorption spectroscopy (AAS) finish.
For the FA with gravimetric finish, 30 g
of the pulp is weighed and added to a crucible, along with 150 g of flux. The material is then carefully homogenized before being
covered by a thin layer of borax.
The mixture is placed in a preheated oven at 1,050°C
± 5°C for 40 to 45 minutes. Once the crucibles have cooled the slag material is separated and discarded with the remaining
material being transferred to a ceramic cup and placed in an oven at a temperature of 950 °C ± 2°C before it is reduced
to 849 °C ± 2°C for 30 minutes in order to evaporate any lead and leave behind a clean doré (Ag/Au).
The doré is carefully weighed on a micro
balance before being transferred to a ceramic cup and dilute nitric acid added until 25 to 75 % of the crucible is filled. The ceramic
pots are placed in an oven for approximately 30 minutes at 110 °C ± 10°C. The pots are
removed from the oven and the silver nitrate solution is decanted leaving the gold. The remaining gold is washed with dilute (4 %) ammonium
hydroxide and then rinsed with distilled water. The calcined crucibles containing the gold are placed into an oven for 10 to 15 seconds
at a temperature of 800 °C. Finally, the crucibles are removed from the oven, cooled and the gold weighed on a microbalance. The gold
and silver contents are calculated using these weights.
The above process is the equivalent of the ALS
Global Method ME-GRA21 (fire assay charge with gravimetric finish).
Fluorine has been analyzed at the Cuzcatlan Laboratory
since mid-2018. As assaying for fluorine was not conducted prior to 2018, the geology department selects drill holes for assaying that
represent areas planned for mining in the near future. Sampling consists of
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making a composite of multiple pulp samples that represent
the full thickness of mineralization for each hole. The composite is then dried for an hour at 105 °C, weighed, with 0.5 ±
0.01 g placed in a zirconium crucible. Approximately 4 ± 0.1 g of sodium peroxide and 1 ± 0.1 g of sodium carbonate are
added to the crucible and homogenized with a glass rod. Next, approximately 1 g of sodium peroxide is added, forming a cover to the
mixture prior to being placed in an oven at approximately 750 ° C ± 50 ° C until the liquid becomes a deep red color, which
is indicative that the sample has melted prior to shaking until total dissolution and allowing to cool to room temperature and the sample
solidifies.
The crucible with its contents is then placed
in a 300 ml beaker with 80 ml of deionized water, where the solids inside the zirconium crucible are dissolved and the solution cooled
to room temperature before being transferred to a 250 ml graduated flask and left to rest for approximately 12 hours.
A 25 ml aliquot is then taken of the sample and
poured into a 100 ml flask, with care taken not to extract sediment. Bromothymol blue is added along with a 25 % HCl solution, 50 ml of
a buffer solution and deionized water. Finally, the contents of the flask are poured into a plastic cup and fluorine levels are analyzed
using a selective ion electrode, based on the calibration curve technique.
ALS Global
Upon arrival at ALS Global’s analytical
facility in Vancouver, British Columbia, the sample identity data were entered into the company’s laboratory information management
system). Analysis consists of the following procedures:
| · | Homogenization and splitting of the samples. |
| · | Analysis for silver by ALS-Global Method ME-ICP41
– aqua regia digestion and inductively coupled plasma (ICP)-atomic emission spectroscopy (AES) finish. |
| · | For samples where silver ICP analysis exceeded
100 ppm the samples were rerun by ALS Global Method Ag-GRA21 – 30 g fire assay charge with gravimetric finish. |
| · | Fire assay for gold by ALS Global Method Au-AA23
– 30 g fire assay charge with AAS finish. |
| · | For samples where gold AAS analysis exceeded
10 ppm the samples were rerun by ALS Global Method Au-GRA21 – 30 g fire assay charge with gravimetric finish. |
| · | Analysis for 34 other elements by ALS-Global
Method ME-ICP41 – aqua regia digestion and ICP-AES finish. |
| · | For samples where lead and zinc ICP analysis
results exceeded 10,000 ppm (1.0 %), the samples were re-run by ALS-Global Method PB-AA46 and Method ZN-AA46 - aqua regia digestion
and AAS finish. |
All laboratory internal quality control results
are reported on the laboratory assay certificates. Sample pulps and rejects were temporarily stored by ALS Global for later shipment back
to the San Jose Mine site.
| 11.3 | Laboratory accreditation |
The onsite laboratory used by Cuzcatlan since
2012 for assaying channel samples was accredited as a testing laboratory having been assessed by the Standards Council of Canada
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(SCC)
and found to conform with the requirements of ISO/IEC 17025:2005 for sample preparation and assaying of silver and gold with accreditation
awarded on March 2, 2018. Prior to this, the laboratory was not certified. The Cuzcatlan Laboratory is not independent of Cuzcatlan
or Fortuna.
The ALS Chemex laboratory used by Cuzcatlan (renamed
to ALS Global) for the submission of drill core up until March 5, 2020, and as an umpire laboratory, is an independent, privately-owned
analytical laboratory group. The Vancouver laboratory holds ISO 17025 accreditation. The Mexican laboratory holds ISO 9001:2000 certification.
The SGS Laboratory used by Cuzcatlan as an umpire
laboratory for drill core is located in Durango, being an independent and privately owned analytical laboratory group. The Durango laboratory
holds ISO/IEC 17025:2005 accreditation for sample preparation and assaying.
Pan American and Continuum used the same ALS Chemex
Laboratory for assaying drill core as Cuzcatlan. Data obtained from the Pan American and Continuum programs represents less than 2 % of
all information collected as of the effective date of this Report.
| 11.4 | Sample security and chain of custody |
Sample collection and transportation of drill
core and channel samples is the responsibility of the Cuzcatlan exploration and mine geology departments.
Exploration core boxes are sealed and carefully
transported to the core logging facilities located adjacent to the mine offices where there is sufficient room to layout and examine several
holes at a time. Once logging and sampling have been performed, the core is transferred to the permanent storage facility at the mine
site. The onsite storage facility is dry and well illuminated, with metal shelving. Core is stored chronologically, and location plans
of the warehouse provide easy access to all core collected by Cuzcatlan.
The drill core from the infill drilling program
is stored in the same warehouse as the exploration core. The storage facility is managed by the Cuzcatlan geology department, and any
removal of material must receive their approval.
Coarse reject material from exploration and infill
drill core is presently being stored securely in a separate warehouse. Pulps from the exploration and infill drill programs are stored
in a secure and dry pulp storage facility.
Coarse reject material from channel samples is
collected from the Cuzcatlan Laboratory every day and stored in a storage facility located in a secure building half a kilometer from
the main operation. Pulps of channel samples analyzed by ALS Global are also stored in the same storage facility as the coarse reject
material. Pulps of channel samples analyzed by the Cuzcatlan Laboratory are stored in a secure storage facility at the operation.
Samples are retained in accordance with the Fortuna
corporate sample retention policy. All drill core and coarse rejects and pulps from the drill core are stored indefinitely and only disposed
of through an official confirmation process submitted by Cuzcatlan and confirmed by Fortuna’s SVP of Technical Services and the
SVP of Exploration. Disposal of coarse rejects from surface samples is performed after 90 days and is controlled by the exploration department.
Disposal of coarse rejects from underground channel samples is performed after 90 days and is the responsibility of the Geology Superintendent.
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| 11.5 | Quality control measures |
The implementation of a quality assurance/quality
control (QAQC) program is a current standard industry practice and involves establishing appropriate procedures and the routine insertion
of certified reference material (CRMs), blanks, and duplicates to monitor the sampling, sample preparation and analytical process. Analysis
of QC data is completed to assess the reliability of sample assay data and the confidence in the data used for the estimation.
Pan American and Continuum did not insert QC samples
during their drill programs. To verify the Continuum results, Fortuna submitted 42 samples representing 14 % of the total assessed samples
for re-analysis, consisting of 23 pulp duplicates and 19 field duplicates (quarter core taken of the remaining half core). The results
were independently reviewed by third-party consultants Resource Modeling Inc. (RMI) who concluded that “there was no significant
bias between the original Continuum assays and the 42 check assays” (Lechner & Earnest, 2009). The QP agrees with this
conclusion. The Pan American and Continuum drilling represents less than 2 % of the total samples assayed at the San Jose Mine, with Cuzcatlan
responsible for assaying the remaining 98 %.
Cuzcatlan routinely inserts certified CRMs, blanks,
field, preparation (coarse reject) and pulp duplicates to the Cuzcatlan and ALS Global laboratories.
The Cuzcatlan
Laboratory has been the primary laboratory for assaying channel samples since February 2012 with the results of the inserted QC samples
detailed below. Prior to this channel samples were sent to ALS Global together with appropriate numbers of CRMs, blanks, and duplicates,
which indicated reasonable levels of accuracy, precision, and no contamination or sample switching issues. These results have not been
detailed in this Report as they correspond to areas that have been mined out. Exploration and infill drill core is sent to the ALS Global
Laboratory with accompanying CRMs, blanks and duplicates with the QC results presented in the following subsections.
Since April 2018, infill drill core has also
been sent to the Cuzcatlan Laboratory (based on it attaining certification) for assaying silver and gold with the appropriate insertion
of QC samples. Since July 20, 2020, exploration drill core has also been submitted to the Cuzcatlan Laboratory. Comment on the results
to date for these inserted QC samples are detailed in the following subsections for completeness.
Quality control measures regarding fluorine levels
are monitored internally by the Cuzcatlan Laboratory as of the effective date of this Report.
| 11.5.1 | Certified reference material |
CRMs are
samples that are used to measure the accuracy of analytical processes and are composed of material that has been thoroughly analyzed to
accurately determine its grade within known error limits. CRMs are inserted by the geologist into the sample stream, and the expected
value is concealed from the laboratory, even though the laboratory will inevitably know that the sample is a CRMs of some sort. By comparing
the results of a laboratory’s analysis of a CRM to its certified value, the accuracy of the result is monitored.
CRMs have been used to assess the accuracy of
the assay results from both the Cuzcatlan and ALS Global laboratories having been placed into the sample stream by Cuzcatlan geologists
to monitor accuracy of the analytical process. CRM results are assessed at the operation on a monthly basis using time series graphs to
identify trends or biases.
Cuzcatlan Laboratory
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Thirty-two different CRMs have been used to monitor
the Cuzcatlan Laboratory since February 2012 with the majority of CRMs (25 of the 32) generated from in-house coarse reject material
and certified by CDN Resource Laboratories Ltd in Vancouver, Canada.
Channels
The Cuzcatlan Laboratory employs a three-acid
digestion methodology with AAS for assaying silver, unless the grade is greater than 500 g/t Ag, in which case the sample is re-assayed
by FA with a gravimetric finish. For gold, the sample is assayed using FA-AAS unless the gold greater is greater than 6.5 g/t Au, in which
case the sample is re-assayed with a gravimetric finish.
Results for the CRMs submitted with the channel
samples to the Cuzcatlan Laboratory are monitored on a continuous basis with a monthly report detailing results to management and actions
taken if any issues are identified. In addition to statistical analysis, graphical analysis of the results is also conducted to assess
trends and biases over time in the data.
Pass rates reported for CRMs submitted with channel
samples since mining commenced to the data cut-off date for silver and gold values are regarded as acceptable. Two of the purchased CRMs
failed to provide representative samples for the assaying process and submission ceased in favor of the in-house CRMs. The Cuzcatlan
Laboratory had some initial issues with its protocols and equipment regarding gold assaying in the second half of 2012 and early 2013.
The laboratory has been through several external audits culminating with its accreditation in 2018 and this work has resulted in continuous
improvement in accuracy levels observed for gold grades.
Drill core
CRMs have been inserted at a submission rate of
1 in every 20 infill drill core samples and Brownfield’s exploration drill core to the Cuzcatlan Laboratory since April 23,
2018, and July 20, 2020, respectively. Results for the CRMs submitted with the drill core samples are monitored on a continuous basis
with a quarterly report detailing results to management and actions taken if any issues are identified. Pass rates reported for CRMs submitted
with core samples for silver and gold values are regarded as acceptable.
ALS Global Laboratory
Drill core (exploration and infill-pre-July 2020
and April 2018, respectively) was sent to ALS Global for assaying. As described above, silver was assayed by ICP-AES, unless the
grade was greater than 100 g/t Ag, in which case the sample was re-assayed by FA with a gravimetric finish.
CRMs to monitor the accuracy of silver assays
have been submitted at a rate of approximately 1 in 20 samples, to assess the accuracy of assays obtained by both ICP-AES and FA with
a gravimetric finish.
Silver accuracy levels of core samples sent to
ALS Global were regarded as reasonable with CRMs for both methods returning pass rates greater than 96 %. This was despite many of the
failures observed for the ICP-AES analysis being attributed to standard CDN-HC-2 which was thought to be inappropriate for ICP-AES analysis.
Gold is assayed by FA-AAS unless the gold concentration
is greater than 10 g/t Au, in which case the sample is re-assayed by FA with a gravimetric finish.
CRMs to monitor the accuracy of gold assays were
submitted at a rate of 1 in 19 samples primarily for assaying by FA-AAS and occasionally by FA with a gravimetric finish.
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Gold accuracy levels of core samples sent to ALS
Global were regarded as reasonable with CRMs for both methods returning pass rates greater than 95 %. It was noted that the CRMs that
tended to fail at a higher rate were those inserted at the beginning of the monitoring program with results improving as time progressed.
Field blank samples are composed of material that
is known to contain grades that are less than the detection limit of the analytical method in use and are inserted by the geologist in
the field. Blank sample analysis is a method of determining sample switching and cross-contamination of samples during the sample preparation
or analysis processes. Cuzcatlan uses coarse marble sourced from a local quarry and provided by an external supplier as their blank sample
material.
Cuzcatlan Laboratory
Channels
The analysis focuses on the submission of blanks
at a submission rate of approximately one in 20 channel samples. Results of the blanks submitted indicate that cross contamination and
mislabeling are not material issues at the Cuzcatlan Laboratory with pass rates greater than 99 %.
Drill core
For blanks submitted to the Cuzcatlan Laboratory
with infill and exploration drill core samples since April 23, 2018, no failures for silver or gold (set at two times the lower detection
limit) were detected, indicating that cross contamination and mislabeling are not material issues at the Cuzcatlan Laboratory.
ALS Global Laboratory
Blanks were submitted with core samples to the
ALS Global Laboratory by Fortuna and Cuzcatlan covering all core submitted at a rate of one in 20 samples. A pass rate for blanks
(set at two times the lower detection limit) of greater than 98 % was achieved for both silver and gold blank submissions. If two blanks
failed in succession, all assay results for the batch were automatically reviewed and re-analyzed if deemed necessary. Blank results from
ALS Global were regarded as acceptable indicating no significant sample switching or contamination.
The precision of sampling and analytical results
can be measured by re-analyzing the same sample using the same methodology. The variance between the measured results is a measure of
their precision. Precision is affected by mineralogical factors such as grain size and distribution and inconsistencies in the sample
preparation and analysis processes. There are a number of different duplicate sample types which can be used to determine the precision
for the entire sampling process, sample preparation, and analytical process. A description of the different types of duplicates used by
Cuzcatlan is provided in Table 11.1.
Table 11.1
Duplicate types used by Cuzcatlan
Duplicate |
Description |
Field |
Sample generated by another sampling operation at the same collection point. Includes a second
channel sample taken parallel to the first or the second half of drill core sample and submitted in
the same or separate batch to the same (primary) laboratory. |
Preparation |
Second sample obtained from splitting the coarse crushed rock during sample preparation and
submitted in the same batch by the laboratory. |
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Laboratory |
Second
sample obtained from splitting the pulverized material during sample preparation and submitted in the same batch by the
laboratory. |
Reject assay |
Second
sample obtained from splitting the coarse crushed rock during sample preparation and submitted blind to the same or different
laboratory that assayed the original sample. |
Duplicate assay |
Second
sample obtained from splitting the pulverized material during sample preparation and submitted blind at a later date to the same
laboratory that assayed the original pulp. |
Check assay |
Second sample obtained from the pulverized material during sample preparation and sent to an umpire laboratory for analysis. |
Numerous plots and graphs are used on a monthly
basis to monitor precision and bias levels. A brief description of the plots employed in the analysis of Cuzcatlan duplicate data, is
described below:
| · | Absolute relative difference (ARD) statistics:
relative difference of the paired values divided by their average. |
| · | Scatter plot: assesses the degree of scatter
of the duplicate result plotted against the original value, which allows for bias characterization and regression calculations. |
| · | Ranked half absolute relative difference (HARD)
of samples plotted against their rank percent value. |
Duplicates were submitted to both the Cuzcatlan
Laboratory (with channel samples) and the ALS Global Laboratory (with drill core). The ALS laboratory also acts as the umpire laboratory,
analyzing reject assays and check assays (pulps) from the Cuzcatlan Laboratory.
If both the original and duplicate result returned
a value less than 10 times the detection limit, the result was disregarded for the ARD analysis due to distortion in the precision levels
at very low grades close to the limits at which the instrumentation can measure. These very low values are not seen as material and can
distort more meaningful results if they are not removed.
Cuzcatlan Laboratory
Channels
Cuzcatlan inserts field duplicates with channel
samples as part of its QAQC program. Preparation and laboratory duplicates are inserted by the laboratory whereas reject assays and duplicate
assays are inserted blind from the geology department. Check assays (both coarse rejects and pulps) from the Cuzcatlan Laboratory are
sent to the certified laboratory of ALS Global to provide an external monitor of precision. CRMs and blanks are also submitted with the
check assays to ensure the accuracy of the ALS results. HARD results for duplicates were used to assess the Cuzcatlan Laboratory.
In general precision levels are reasonable with
the majority of HARD values being less than the accepted threshold value. However, field duplicate results are poor for both silver and
gold. The operation has tested numerous practices to improve the sampling procedure, such as including: closer supervision of the sampling
process; increasing the sampling mass; trying alternative sampling methods with limited success. In addition, several adjustments have
been made by the laboratory to improve the gold analytical techniques with improvements seen over the years.
Duplicate coarse reject and pulps sent to an umpire
laboratory indicate reasonable precision levels between laboratories, suggesting the issue with the field duplicates is not a Cuzcatlan
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Laboratory issue. This was further confirmed by Cuzcatlan when a program of homogenizing and splitting field samples under controlled
conditions in the laboratory prior to submission to the total sample stream returned reasonable precision levels.
Based on the above, the poor precision levels
for the field duplicates have been attributed to the heterogeneous nature of the mineralization with the presence of a moderate to high
nugget effect. It is worth noting that the results observed for the precision levels for the channel samples are similar to that for drill
core, suggesting that sampling error is not the problem.
Drill core
A full array of duplicate samples has been used
to assess precision levels in respect to drill core sample analysis at the Cuzcatlan Laboratory with number of duplicate submissions ranging
from rate of approximately one in 20 for field duplicates to a rate of one in 40 for reject assays. Results are very similar to those
described for the channel samples and confirm conclusions regarding precision levels.
ALS Global Laboratory
Cuzcatlan primarily relied on the insertion of
field duplicates, reject assays (coarse rejects) and duplicate assays (pulps) to assess the precision of drill core results from the ALS
Global laboratory. The operation also monitored the results of the in-house preparation and laboratory duplicates inserted by ALS.
Cuzcatlan regularly sends check assays (both coarse
rejects and pulps) to the umpire laboratory, SGS, to provide an external monitor of precision. CRMs and blanks are also submitted with
the check assays to monitor the accuracy of the SGS laboratory.
Precision results for exploration core samples
evaluated by ALS Global, expressed as HARD are detailed in Table 11.8.
Precision results for exploration core samples
demonstrate a high level of variability that is representative of the nature of mineralization with poor precision results for the field
duplicates, reject assays and duplicate assays. However, it was discovered during an audit of the results that the exploration team had
been tending to insert low-grade samples (<60 g/t Ag) and this has had a detrimental effect on the results. When higher-grade
values are assessed the precision levels improve and are seen to be acceptable, which is reflected in the superior results observed for
the samples assayed with a gravimetric finish.
Results from the SGS laboratory return similar
precision levels suggesting the issue is not specific to ALS Global.
Precision levels of field duplicates for infill
and exploration drill core samples submitted to ALS Global are regarded as poor. The results are indicative of the highly variable ‘nuggety’
nature of the mineralization that reduces precision levels. The operation has assessed the nugget effect by crushing and splitting the
core to obtain a ‘field split’ prior to submission to ALS Global rather than using the other half of the core. Results indicate
that precision is not an issue at the laboratory but is inherent in the sample and generated due to splitting of the core.
Cuzcatlan continues to monitor and attempt to
improve the precision of the sampled drill core; however, the results indicate the difficulty the variable grades present for grade estimation,
particularly for gold.
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| 11.5.4 | Conclusions regarding quality control results |
Accuracy (CRM submission) and sample contamination/switching
(blank submission) for both laboratories is reasonable, with the Cuzcatlan Laboratory making some significant improvements in its gold
accuracy since 2013. Precision remains a problem with field duplicate results below the expected levels at both the ALS Global and Cuzcatlan
laboratories. Precision levels for field duplicates have improved over time as the operation has worked hard at improving their sampling,
preparation and analytical techniques but is still falling short of the target levels. The fact that both sample types (drill core and
channels) return lower than expected precision results for field duplicates, along with the results of testing ‘field splits’,
supports the theory that the style of mineralization is inherently variable and obtaining a large enough sample mass to counteract this
variance is impractical. The failure to reproduce similar grades in the same sample does mean that there is a slightly higher level of
uncertainty in the estimate, particularly for gold, and that some variation between the estimate and reality as reported in the reconciliation
should be expected. However there does not appear to be a definitive bias to the results and the variation has been taken into account
during Mineral Resource confidence classification.
| 11.6 | Comment on Section 11 |
Implementation of a QAQC program is current industry
practice and involves establishing appropriate procedures and the routine insertion of CRMs, blanks, and duplicates to monitor the sampling,
sample preparation and analytical process. Fortuna implemented a full QAQC program to monitor the sampling, sample preparation and analytical
process since taking control of the San Jose Project in 2006 in accordance with its companywide procedures. The program involved the routine
insertion of CRMs, blanks, and duplicates. Evaluation of the QAQC data indicates that the data are sufficiently accurate and precise to
support Mineral Resource estimation.
The style of mineralization does present problems
primarily with precision levels due to the “nugget effect” and subsequently some variations between the estimate and reality
can be expected on a local scale. The gold assays are likely to present the biggest variation and the operation must continue to improve
the channel sampling process to improve repeatability to increase the confidence in the block model estimates and grade control grades.
It is the opinion of the QPs that the sample preparation,
security, and analytical procedures used at the San Jose Mine for samples sent to both the ALS Global and Cuzcatlan laboratories have
been conducted in accordance with acceptable industry CRMs, and that assay results generated following these procedures are suitable for
use in Mineral Resource and Mineral Reserve estimation.
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| 12.1.1 | Pan
American and Continuum |
Information regarding
the verification of data conducted by Pan American and Continuum was not available for this Report.
Continuum results
were verified by Fortuna with the resubmission of 42 samples representing 14 % of the total samples assayed, with no major differences
noted between the results. The Pan American and Continuum drilling represents less than 2 % of the total samples assayed at the San Jose
Mine, with Cuzcatlan responsible for assaying the remaining 98 %.
Since taking ownership
in 2009 Cuzcatlan mine site staff have adhered to a stringent set of procedures for data storage and validation, performing verification
of its data on a monthly basis for all data relating to drilling and channel samples. The operation employs a Database Administrator
who is responsible for oversight of data entry, verification and database maintenance.
Steps taken by
the Qualified Persons to verify the data used in the Mineral Resource and Mineral Reserve estimation process and detailed in this Report
include evaluation of the following areas:
| · | Collars
and down-hole surveys. |
| · | Geological
logs and assays. |
| · | Geotechnical
and hydrology. |
| · | Metallurgical
recoveries. |
| · | Mineral
Resource estimation. |
| · | Mineral
Reserve estimation |
Prior to 2017,
the Cuzcatlan data used for Mineral Resource estimation was stored in two SQL databases, one for storing channel data and the other for
drill hole data. The databases were fully validated annually by Fortuna as part of the Mineral Resource estimation process.
In mid-2017, Cuzcatlan
worked with staff from Maxwell Geoservice to transfer all information into the commercial SQL database system, Datashed, employing a
dedicated Data Manager to oversee the data transfer. All data must pass a series of validation checks prior to being imported into Datashed.
In addition, an
independent audit of the database is conducted every quarter by a dedicated Database Auditor. A report is filed listing any discrepancies
and Cuzcatlan staff are required to make the necessary corrections.
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A further preliminary
validation of the database was performed by the Cuzcatlan geology department in June 2023 prior to usage for resource updating.
The database was
then reviewed and validated by Mr. Alexander Delgado (MAusIMM) and Mr. Chapman. The data verification procedure involved the
following:
| · | Evaluation
of minimum and maximum grade values. |
| · | Investigation
of minimum and maximum sample lengths. |
| · | Randomly
selecting assay data from the database and comparing the stored grades to the original assay
certificates. |
| · | Assessing
for inconsistencies in spelling or coding (typographic and case sensitivity errors). |
| · | Ensuring
full data entry and that a specific data type (collar, survey, lithology, and assay) is not
missing. |
| · | Assessing
for sample gaps or overlaps. |
No significant
inconsistencies were discovered.
| 12.3 | Collars and downhole surveys |
Mr. Chapman
checked randomly selected collar and downhole survey information for each campaign against source documentation. In addition, Mr. Chapman
completed a comparison of the underground collar coordinates against the surveyed underground developments and drill stations. The wireframes
showed a good correlation with collar locations recorded in the database.
Downhole surveys
are taken using survey equipment such as Flexit or Reflex tools. A validation of the readings was performed by Mr. Chapman by randomly
selecting readings taken from individual holes and assessing the level of deviation between successive data points. If significant discrepancies
(e.g. > 15%) existed between data points, the information was flagged and follow up checks performed. Mr. Chapman is of the opinion
that collar and downhole survey data has been determined using appropriate techniques and is suitable for usage in Mineral Resource and
Mineral Reserve estimation.
| 12.4 | Geological logs and assays |
In early 2018 Cuzcatlan
initiated the usage of the Maxwell LogChief software that supports the electronic collection of geological and geotechnical information
in the field using a standardized system of drop-down menus to promote consistency. In addition, all information is electronically transferred
to the database removing the risk of transcription errors.
For validation
purposes, Mr. Weedon, during site visits, reviews the geological interpretation and drill core with Cuzcatlan exploration personnel.
Assays received
by Cuzcatlan are reported in both portable document format (pdf) and Microsoft Excel format. Documents are compared and only imported
into the database if they are in agreement. Importation is performed electronically without requiring transcription.
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Assay data are
verified using a full QAQC program including the insertion of CRMs, blanks and duplicates for assays reported by both Cuzcatlan and ALS
Global laboratories. A full description of this program and its results is provided in Section 11.5.
To further verify
the assay data, Mr. Chapman randomly selected assay data from the database and compared the assay results stored to that of the
original assay certificates. Mr. Chapman is of the opinion that the geological and assay data stored in the database is representative
of that reported from the laboratories and is suitable for usage in Mineral Resource and Mineral Reserve estimation.
| 12.5 | Geotechnical
and hydrogeology |
Mr. Veillette
has been providing technical support with respect to tailings and water management since September 2022. Mr. Veillette has
assisted SRK consulting, the Engineer of Record (EoR), in the management of the tailings facilities and reviewed all technical documents
related to tailings and water management. The San Jose Mine has a water balance with a closed circuit where effluent is not discharged
and only water treatment water from the nearby community is used as required. As of the effective date of this Report, it is the opinion
of Mr. Veillette that the partially closed tailings dam is well managed with approximately 2 m of freeboard below the spillway
invert; and the dry stack is also well managed.
| 12.6 | Metallurgical recoveries |
A daily log is
produced by Cuzcatlan staff that monitors the performance of the plant including the metallurgical recovery achieved for each metal produced.
This daily log is supplemented with a monthly plant reconciliation report that reconciles the head grades with the concentrate and tailings
grades to verify the recoveries being achieved at the operation. Ms. Gonzalez received a copy of the above information and used
this data to check that the proposed metallurgical recoveries set out in this Report are achievable and reasonable.
Ms. Gonzalez
is also responsible for reviewing and approving any adjustments to the process design or metallurgical testwork programs while her day-to-day
activities include verifying plant operations, overseeing installation of new equipment, fine-tuning the current operational strategy,
and discussing aspects of mineralogy, lithology and operational issues with the site staff.
In addition to
reviewing daily plant performance, Ms. Gonzalez also conducted ongoing reviews of processing performance as part of her duties including:
| · | Review
of monthly and quarterly metallurgical balance of the processing plant. |
| · | Metallurgical
testwork programs of drill core. |
| · | Historical
statistical processing plant performance. |
| · | Overseeing
installation of new plant equipment. |
| · | Fine-tuning
operational strategy. |
| · | Discussing
aspects of mineralogy, lithology and operational issues with site staff. |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
| 12.7 | Mineral Resource estimation |
The Mineral Resource
estimation methodology followed by Cuzcatlan, as described in Sections 14 of this Report, is defined in Fortuna’s MRMR procedural
manual, which is based on CIM (2019) best practice guidelines.
Each step of the
process is documented, and a checklist developed that is signed off by Cuzcatlan staff and Mr. Delgado.
Validation of data
used in the estimates from Mr. Chapman includes the following reviews:
| · | Site
visit to review core, underground workings and discuss estimation methodology. |
| · | The
database (as described above). |
| · | Wireframe
modeling to define geological, structural and mineralization domains. |
| · | Statistical
evaluation to confirm domaining is appropriate and adheres to the geological interpretation. |
| · | Variographic
analysis to confirm modeled variograms correspond to experimental variography. |
| · | Cross
validation and reconciliation results. |
| · | Statistical
checks on each field contained in the resource block model to confirm minimum/maximum values
are not exceeded. |
| · | Mineral
Resource classification. |
| · | Depletion
of mined out and remnant/isolated blocks from the model. |
| · | Reported
Mineral Resources correspond with block model. |
The QP is of the
opinion that the Mineral Resource estimation was performed using standard industry practices and is suitable for usage in Mineral Reserve
estimation.
| 12.8 | Mineral
Reserve estimation |
The Mineral Reserve
estimation methodology followed by Cuzcatlan, as described in Section 15 of this Report, is defined in Fortuna’s MRMR procedural
manual, which is based on CIM (2019) best practice guidelines.
Each step of the
process is documented, and a checklist developed that is signed by Cuzcatlan staff and Mr. Espinoza.
Mr. Espinoza
has visited the San Jose Mine several times during 2022 and 2023 to verify the mine infrastructure, mine operating practices, as well
as the conditions of the rock mass for overhand cut and fill and sublevel longhole stoping as described in Section 16. Mr. Espinoza
holds regular virtual meetings with the Cuzcatlan operations management and technical services to review operational results on a monthly
basis. Additionally, he is responsible for peer reviewing any technical studies relating to operational improvements associated with
the mining methods.
Other reviews made
to support the Mineral Reserve estimation process at the San Jose Mine include:
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| · | Ensuring
all aspects of Mineral Reserve estimation and reporting adhere to Fortuna’s “Technical
Information Policy”. |
| · | Reviewing
and confirming parameters used for NSR evaluation adhere to Fortuna’s “Procedure
for NSR point value”. |
| · | Reviewing
and confirming parameters used for cut-off grade calculation adhere to Fortuna’s “Procedural
Manual for COG determination” and CIM best practices. |
| · | Reviewing
and confirming operational parameters used in the estimation of Mineral Reserves are based
on current market and operational considerations and conform to CIM best practices. |
| · | Reviewing
historical mining dilution and recovery with Cuzcatlan technical services to verify parameters
used in the estimation process are reasonable. |
| · | Discussions
regarding MSO optimization results with the Cuzcatlan technical services and mine operations
departments. |
| · | Reviewing
various LOM scenarios and their operational applicability to determine the optimal LOM based
on Fortuna’s strategic goals. |
| · | Review
of monthly mine reconciliation results (see below). |
Cuzcatlan performs
a reconciliation of the resource and reserve block model estimates against production following a corporate procedural manual on a monthly
basis and reports these results to Fortuna. Mr. Chapman and Mr. Espinoza are responsible for reviewing and validating the results
reported and ensuring any discrepancies greater than 15 % are investigated and reasons for the variation explained.
Historical mine
reconciliation results indicate that the estimation methodology is reasonable, and production has reconciled well with the estimates
throughout the history of production at the mine.
The QPs performed
site visits and personal inspections as outlined in Section 2.3 of the Report.
| 12.11 | Comment on Section 12 |
The QPs are of
the opinion that the data verification programs performed on the data collected from the mine are adequate to support the geological
interpretations, the analytical and database quality, and Mineral Resource and Reserve estimation at the San Jose Mine and that, to the
knowledge of the QPs there are no limitations on or failure to conduct such verification that would materially impact the results. This
conclusion is based on the following:
| · | Site
visits conducted by all QP’s to review data and observe operational activities relating
to their area of expertise at the mine. |
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| · | No
material sample biases were identified from the QAQC programs. Analytical data that were
considered marginal were accounted for in the resource classifications. |
| · | Sample
data collected adequately reflect deposit dimensions, true widths of mineralization, and
the style of the deposits. |
| · | Quarterly
reviews of the database producing independent assessments of the database quality. No significant
problems with the database, sampling protocols, flowsheets, check analysis program, or data
storage were noted. |
| · | Cuzcatlan
compiles and maintains a relational database (Datashed) for the San Jose Mine which contains
all collar, assay, density, survey and lithology information as well as all associated QAQC
data. |
| · | Drill
hole and channel collar and downhole surveys are conducted using standard industry techniques. |
| · | All
geologic and assay data is electronically collected and imported into the database eliminating
the potential for transcription errors. |
| · | Geotechnical
and hydrology data indicates that the mining method is suitable based on rock stability and
the plant has sufficient access to water to meet its requirements. |
| · | Metallurgical
recoveries continue according to historical behavior. |
| · | Metallurgical
monitoring is conducted using tests, assays and mineralogical data. |
| · | Drill
data is verified prior to Mineral Resource estimation, by running a software program check. |
| · | Mineral
Resource estimation methodology is verified by Mr. Chapman with each stage being reviewed
and checklists provided. |
| · | Mineral
Reserve estimation methodology is verified by Mr. Espinoza with each stage being reviewed
and checklists completed. |
| · | Monthly
mine reconciliation reports monitor the performance of the resource and reserve block model
estimates and indicate a high level of accuracy with production results typically within
±10 %. |
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| 13 | Mineral Processing and Metallurgical
Testing |
Initial metallurgical
test work to assess the optimum processing methodology for treating ore from the Trinidad deposit was conducted by METCON Research (METCON)
in 2009 and reported in the prefeasibility study prepared by CAM (2010). The following provides a summary of the metallurgical work conducted
and includes comments regarding the most recent studies and findings from the process plant.
METCON completed
testwork on 10 composite samples representing a variety of mineralization styles from the Trinidad deposit. The test work included the
following:
| · | Bond
ball mill work index. |
| · | Rougher
flotation test work with three stages of cleaning. |
| · | Locked
cycle flotation test work. |
| · | Rougher
kinetics flotation. |
A summary of the
relevant information obtained in respect to the above test work is detailed in the following subsections.
In 2022, 25 samples
were tested to establish the metallurgical characteristics of the Victoria mineralized zone. Metallurgical recoveries obtained from samples
with silver head grades ranging from 120 to 160 g/t were 87.74 to 90.11 % for gold and 88.13 to 89.71 % for silver. Based on the results,
it was concluded that mineralization from Victoria follows the same metallurgical recovery trend as the current operation experiences.
Additionally, mineralogical studies did not detect mineral types different from what is currently being processed from the Trinidad deposit.
| 13.1.1 | Whole
rock analysis |
The whole rock
analysis conducted on the variability composite samples showed that quartz is the main gangue mineral, and the samples are amenable to
gold and silver recoveries by flotation CAM, 2010).
Cuzcatlan conducted
additional whole rock analysis tests on more than 40 separate composites between September 2012 and June 2016. The tests provided
similar results to the original 10 composites evaluated and confirmed that these were representative of the Trinidad deposit mineralization
style.
| 13.1.2 | Bond ball mill work index |
. METCON performed
the first Bond ball mill grindability testwork in 2009 as part of the prefeasibility study, obtaining values ranging between 14.35 and
19.20 kWh/t for the samples assessed. The upper value of 19.20 kWh/t was used for design purposes.
Cuzcatlan has conducted
monthly Bond work index (BWi) tests since early 2012. In all cases, composite samples were sent to SGS Minerals Services, Durango and
Mexican Geological Services, Oaxaca. Results range from 15.5 to 20.3 kWh/t, averaging 17.7 kWh/t.
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The results of
the test work indicate that the average BWi is lower than the plant design and should result in less power being required than was predicted.
However, the results also show that there are some cases where the BWi is equal to the design so that the plant is prepared to treat
all material without any process losses.
| 13.1.3 | Locked cycle flotation |
The METCON study
included testing locked cycle flotation using two stages of grind on the composite samples. The conclusions of this study as summarized
in the CAM (2010) prefeasibility study were as follows:
| · | The
metallurgical data indicated that average concentrate grades of 74 g/t for gold and
6,676 g/t for silver may be produced on the composite sample using a two-stage grind
process. |
| · | Gold
and silver average recoveries of approximately 90 % gold and 88 % silver may be produced
on the composite sample. |
| · | Iron
contained in the precious metal concentrate impacts the precious metal concentrate grade. |
| · | Further
metallurgical testing should be conducted to study pyrite depression on the final precious
metal concentrate. |
Results obtained
from the plant since 2012 are detailed in Table 13.1.
Table
13.1 Plant concentrate and recovery values since 2012
Composite
period |
Head
Grade |
Concentrate
grade |
Recovery |
Ag
(g/t) |
Au
(g/t) |
Ag
(g/t) |
Au
(g/t) |
Ag
(%) |
Au
(%) |
2012 |
188 |
1.74 |
6,284 |
57.77 |
87.52 |
86.79 |
2013 |
194 |
1.46 |
5,977 |
45.01 |
88.61 |
88.94 |
2014 |
226 |
1.72 |
6,833 |
52.06 |
89.40 |
89.52 |
2015 |
234 |
1.83 |
7,190 |
56.20 |
91.40 |
91.26 |
2016 |
228 |
1.72 |
7,906 |
59.41 |
92.36 |
92.07 |
2017 |
247 |
1.88 |
7,509 |
56.94 |
92.02 |
91.70 |
2018 |
260 |
1.75 |
8,685 |
58.25 |
91.75 |
91.56 |
2019 |
252 |
1.57 |
8,114 |
50.40 |
90.92 |
90.49 |
2020 |
224 |
1.38 |
6,491 |
39.80 |
91.52 |
91.34 |
2021 |
209 |
1.29 |
6,444 |
39.50 |
91.74 |
91.28 |
2022 |
191 |
1.14 |
5,673 |
33.60 |
91.35 |
90.40 |
2023 |
171 |
1.06 |
4,899 |
30.10 |
90.96 |
90.18 |
Results obtained
from the plant are comparable to those used in the design process.
During 2021, detailed
flotation tests were performed by the Cuzcatlan metallurgical department, where more representative samples were used to predict the
metallurgical recovery for the 2022 and 2023 years. The average recovery results were 90.47 % gold and 91.30 % silver.
Operational results
for 2022 and 2023 (Table 13.1) demonstrated sustained recoveries of 91 % for silver and 90 % for gold could be achieved, with these
levels being confirmed from laboratory tests of representative samples taken from the mine. Current LOMP recoveries are forecast to be
maintained at these levels.
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Metallurgical recovery
is found to vary according to the grade of material processed, with recovery of low-grade ore averaging 85 to 87 % whereas recovery of
high-grade ores can be up to 94 %.
| 13.1.4 | Thickening
and Filtering |
A further difference
between the plant design and functionality has been in the amount of flocculent required for thickening and filtering process of the
tailings and concentrate. The CAM (2010) prefeasibility study had recommended the usage of 40 g/t to 60 g/t of the reagent HychemAF304
for thickening of tailings to achieve solid content of 47 to 51 %. Cuzcatlan has performed the thickening of tailings using the
reagent Magnafloc 336 at the lower concentrations of 15 g/t to 25 g/t and producing tailings with approximately 55 % solid content.
The reagent HychemAF304
(recommended at 25 g/t to 40 g/t concentrations) was also replaced with Magnafloc336 (5 g/t to 10 g/t concentrations) for thickening
the concentrate with no detrimental effect to the solid content percentage. In this way the plant has made significant cost savings by
reducing the quantity of flocculant used in the plant.
Section 17
includes additional information on the plant metallurgical recovery.
In late 2017 it
was observed that levels of fluorine were increasing in the concentrate with the Cuzcatlan financial department reporting that penalties
were occasionally being applied by the purchaser in accordance with the commercial terms.
Currently, it has
been possible to reduce the concentration of this element by up to 50 percent. Therefore, the concentration observed in the final concentrate
will be half of the concentration of fluorine fed into the plant and penalty payments are expected only on very high concentrations fed
(>2,000 ppm F), based on the current sales contract. This penalty level is taken into account in the financial analysis that supports
the Mineral Reserves estimate.
Silver minerals
associated with hematite (iron-oxide) have been identified in ore processed from mineralization from the highest levels of the mine.
The higher iron-oxide content is estimated to be present in 30 % of the mineralization planned for processing. Elevated iron-oxide content
has been found to lower metallurgical recovery in the plant by approximately 5 %. Metallurgical testwork has been initiated to determine
the optimized way to process this material to maximize recovery through processing in batches.
| 13.3 | Comment on Section 13 |
It is the opinion
of the QP that the San Jose Mine has an extensive body of metallurgical investigation comprising several phases of testwork as well as
an extensive history of treating ore at the operation since 2011. In the opinion of the QP, the San Jose metallurgical samples tested
and the ore that is presently treated in the plant is representative of the material included in the LOMP in respect to grade and metallurgical
response. Metallurgical recovery is estimated to be constant for the LOMP at 90.54 % for silver and 89.82 % for gold. Differences between
vein systems are minimal with regard to recovery.
Deleterious elements
detected in ore in specific parts of the deposit have the potential to affect economics due to potential smelting penalties, including
elevated levels of fluorine (>1,000 ppm) or metallurgical recovery, in the case of iron-oxide content. These levels have been considered
in the financial analysis.
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Technical Report |
| 14 | Mineral Resource Estimates |
The following chapter
describes the Mineral Resource estimation methodology of the veins at the San Jose Mine. The Mineral Resource estimate discussed in this
section relates to the Trinidad deposit and Victoria mineralized zone located between UTM coordinates 1846500N and 1847750N (Datum NAD
1927, UTM Zone 14N).
Mineral Resources
were prepared by Jose Callirgos of Cuzcatlan under the technical supervision of Alexander Delgado (MAusIMM) with peer review by Eric
Chapman (P. Geo.). Mr. Delgado and Mr. Chapman are Qualified Persons as defined in National Instrument 43-101, both being
employees of Fortuna. Mineral Resources are estimated and reported as of June 30, 2023.
| 14.2.1 | Known issues that materially affect
Mineral Resources |
Fortuna does not
know of any issues that materially affect the Mineral Resource estimates. These conclusions are based on the following:
| · | Environmental:
Cuzcatlan is in compliance with all material Environmental Regulations and Standards
set in Mexican Law and has complied with all material laws, regulations, norms and standards
at every stage of operation of the mine, as detailed in Section 20. |
| · | Permitting:
To the extent known, all permits that are required by Mexican law for the mining operation
have been obtained. |
| · | Legal:
Cuzcatlan has represented that it is dealing with any legal matters that arise, as detailed
in Section 4.4 of this Report and that currently the mine is operating according to
all legal requirements. |
| · | Title:
Cuzcatlan has represented that the mineral and surface rights have secure title. |
| · | Taxation:
No known issues. |
| · | Socio-economic:
Cuzcatlan has represented that the operation has community support from the local town of
San Jose del Progreso. |
| · | Marketing:
No known issues. |
| · | Political:
Cuzcatlan believes that the current government is supportive of the operation. |
| · | Other
relevant issues: No known issues. |
| · | Mining:
No known issues. |
| · | Metallurgical:
Cuzcatlan presently successfully treats ore extracted from the San Jose Mine in the onsite
processing plant to produce a silver concentrate with gold credits. This work has been described
in Section 13. |
| · | Infrastructure:
No known issues. |
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| 14.3 | Assumptions, methods and parameters |
The 2023 Mineral
Resource estimates were prepared via ordinary kriging (OK) in veins associated with the Trinidad deposit and the Victoria mineralized
zone (main vein) based on the following steps:
| · | Data
validation as performed by Fortuna. |
| · | Data
preparation including importation to various software packages. |
| · | Geological
interpretation and modeling of mineralization domains. |
| · | Coding
of drill hole and channel data within mineralized domains. |
| · | Sample
length compositing of both drill holes and channel samples. |
| · | Exploratory
data analysis of the key constituents: silver, gold, lead, zinc, copper, fluorine and density. |
| · | Analysis
of boundary conditions. |
| · | Declustering
of key constituents. |
| · | Analysis
of extreme data values and application of top cuts. |
| · | Variogram
analysis and modeling of normal score distributed data. |
| · | Determination
of estimation and search parameters based on kriging neighborhood analysis (KNA). |
| · | Estimation
of silver, gold, lead, zinc, copper, fluorine grades by OK, IDW, and value assignment
where insufficient samples are available for interpolation. |
| · | Depletion
of blocks identified as extracted or inaccessible. |
| · | Classification
of estimates with respect to 2014 CIM guidelines. |
| · | Mineral
Resource tabulation and reporting. |
| · | Risk
analysis of silver and gold estimates through conditional simulation. |
| 14.4 | Supplied data, data transformations
and data validation |
Cuzcatlan information
used in the 2023 estimation is sourced from Maxwell’s Datashed industry-standard database for the Project.
Supplied data included
all information available as of June 30, 2023, and was provided by Cuzcatlan.
| 14.4.1 | Data
transformations |
All data is stored
using the same UTM coordinate system (NAD 1927, UTM Zone 14N) and the same unit convention. Transformations of the supplied drill hole
and channel information, including assay grades, were not required.
Mineral Resource
estimates have used several software packages for undertaking modeling, statistical, geostatistical and grade interpolation activities.
Wireframe modeling of the mineralized envelopes was performed in Leapfrog Geo version 2022.1. Data preparation,
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block modeling and grade
interpolations were performed in Datamine RM version 1.6.75. Declustering, statistical and variographic analysis was performed in Supervisor
version 8.15. Normal score transformations, sequential Gaussian simulation, and re-blocking of simulations for risk analysis were performed
using the Geostatistical Software Library (GSLIB).
Collar, survey,
lithology, and assay data exported from Datashed database were provided by Cuzcatlan in Access format and imported into Datamine RM to
build 3D representations of the drill holes and channels. Assay values at the detection limit were adjusted to half the detection limit.
Absent assay values were adjusted to a zero grade. In areas that were estimated (Trinidad deposit and Victoria mineralized zone), a total
of 327 surface core drill holes and 995 underground core drill holes totaling 410,817.95 m and 35,093 channels totaling 150,322.16 m
were available for Mineral Resource estimate support (Table 14.1). Only a portion of the 561,140 m of data have been assayed. Fortuna/Cuzcatlan
have been responsible for collecting 99 % of the data.
Table
14.1 Data used in the 2023 Mineral Resource update of the Trinidad deposit and Victoria mineralized zone
Company |
Sample
Type |
Count |
Meters |
Percent
of Total |
Fortuna/Cuzcatlan |
Surface
Core Drill holes |
311 |
115,820.65 |
21 |
Underground
Core Drill holes |
995 |
289,775.80 |
52 |
Underground
Channels |
34,918 |
149,610.03 |
27 |
Sub-total |
36,224 |
563,222.53 |
99 |
Continuum |
Surface
Core Drill holes |
13 |
4,370.00 |
1 |
Underground
Channels |
175 |
712.13 |
0 |
Sub-total |
188 |
5,082.13 |
1 |
Pan
American Silver |
Surface
Core Drill holes |
3 |
851.50 |
0 |
TOTAL |
36,415 |
561,140.11 |
100 |
An extensive data
validation process was conducted by Cuzcatlan and Fortuna prior to the Mineral Resource estimation with a more detailed description of
this process provided in Section 12.
Validation checks
were also performed upon data importation into Datamine mining software and included searches for overlaps or gaps in sample and geology
intervals, inconsistent drill hole identifiers, and missing data. No significant discrepancies were identified.
| 14.5 | Geological
interpretation and domaining |
Mineralization
at the San Jose Mine is typical of a low-sulfidation epithermal-style deposit having formed in a relatively low temperature, shallow
crustal environment. Silver–gold mineralization is hosted by hydrothermal breccias, crackle breccias, quartz/carbonate veins and
zones of sheeted and stockworked quartz/carbonate veins emplaced along steeply-dipping north- and north–northwest-trending fault
structures. The main silver–gold bearing species are acanthite (argentite) and electrum. Host rocks consist of andesitic to dacitic
subaerial and subaqueous lava flows of presumed Paleogene age.
Major vein systems
recognized in Trinidad and Victoria all have a general north to south strike orientation and near vertical dip. Veins were divided into
two classes according to the extent of exploration and mineralization. Primary veins have extensive exploration
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from both drilling and
underground extraction and are well-understood in terms of geological and grade continuity. Secondary domains have been subjected to
very limited exploration and have not been estimated due to the low level of confidence in the geological continuity at this stage of
exploration. Statistical analysis of intervals intersecting the interpreted secondary structures has been included for completeness,
but no additional evaluation has been conducted.
Primary domains
| · | Bonanza
(Bv), Trinidad (Tv), Stockwork (Swk), and Stockwork2 (Swk2), Fortuna (Fv), Paloma (Pv), Bonanza
HW splay (Bhws), Trinidad FW splay (Tfw), Trinidad FW2 splay (Tfw2), Trinidad FW3 splay (Tfw3),
Trinidad HW splay (Thws4), Stockwork3 (Swk3), Stockwork4 (Swk4), Victoria main structure
(Vmz), and Victoria HW1 (Vhwz1). |
Secondary domains
| · | Narrow
vein1 (Nwv1), Sk vein2 (Sk02), Sk vein3 (Sk03), Sk vein6 (Sk06), Diedro (Dd2), Victoria HW2
(Vhwz2), and Victoria HW3 (Vhwz3). |
Mineralized envelopes
to define each vein were constructed in Leapfrog Geo software by the Cuzcatlan mine geology and exploration departments based on the
interpretation of the deposit geology and refined using the drill hole, channel and underground mapping information. A three-dimensional
perspective of the wireframes representing the veins is displayed in Figure 14.1. Oxide domains are not present.
Figure
14.1 3D perspective of Trinidad and Victoria deposits showing vein wireframes
|
Figure
prepared by Cuzcatlan, 2023 |
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| 14.6 | Exploratory data analysis |
| 14.6.1 | Compositing of assay intervals |
Compositing of
sample lengths was undertaken so that the samples used in statistical analyses and estimations have similar support (i.e., length). Cuzcatlan
samples drill holes and channels at varying interval lengths depending on the length of intersected geological features and the true
thickness of the vein structure. Sample lengths were examined for each vein. The majority of samples (>99 %) were sampled on lengths
of 2 m or less as demonstrated in Figure 14.2.
Figure
14.2 Length of samples assayed
Figure prepared by Cuzcatlan,
2023 |
Based on the average
sampling length and the selective mining unit a 2 m composite was chosen as suitable for all veins.
The Datamine COMPDH
downhole compositing process was used to composite the samples within the estimation domains (i.e., composites do not cross over the
mineralized domain boundaries). The COMPDH parameter MODE was set to a value of one to allow adjusting of the composite length while
keeping it as close as possible to the composite interval, so as to minimize sample loss. The composited and raw sample data were compared
to ensure no sample length loss or metal loss had occurred.
This methodology
results in a variance in the composite length distributed around the 2 m composite interval. To ensure a bias is not present due to the
variance in composite length, a comparison of silver and gold grades to composite length was conducted and no relationship was determined
to be present.
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| 14.6.2 | Statistical
analysis of composites |
Exploratory data
analysis was performed on composites identified in each geological vein (Table14.2). Statistical and graphical analysis (including histograms,
probability plots, scatter plots) were investigated for each vein to assess if additional sub-domaining was required to achieve stationarity.
Table
14.2 Univariate statistics of undeclustered drill hole and channel composites by vein
Vein |
Grade |
Count |
Minimum |
Maximum |
Mean |
SD |
CV |
Bonanza |
Ag
(g/t) |
16,243 |
0 |
11,710 |
211 |
446 |
2.11 |
Au
(g/t) |
16,243 |
0 |
123.40 |
1.89 |
4.30 |
2.27 |
Pb
(ppm) |
10,024 |
2 |
71,656 |
479 |
1,877 |
3.92 |
Zn
(ppm) |
4,564 |
13 |
43,648 |
393 |
1,869 |
4.75 |
Cu
(ppm) |
4,564 |
2 |
6,030 |
55 |
195 |
3.53 |
Trinidad |
Ag
(g/t) |
9,282 |
0 |
10,200 |
178 |
427 |
2.40 |
Au
(g/t) |
9,282 |
0 |
74.11 |
1.01 |
2.51 |
2.47 |
Pb
(ppm) |
6,239 |
1 |
117,295 |
594 |
2,742 |
4.61 |
Zn
(ppm) |
2,270 |
4 |
227,466 |
996 |
6,742 |
6.77 |
Cu
(ppm) |
2,270 |
1 |
7,092 |
74 |
266 |
3.61 |
Stockwork |
Ag
(g/t) |
33,598 |
0 |
20,320 |
304 |
727 |
2.39 |
Au
(g/t) |
33,598 |
0 |
460.78 |
2.22 |
6.59 |
2.98 |
Pb
(ppm) |
31,555 |
2 |
61,216 |
758 |
1,884 |
2.49 |
Zn
(ppm) |
3,764 |
12 |
49,845 |
1,018 |
2,333 |
2.29 |
Cu
(ppm) |
3,764 |
2 |
5,063 |
100 |
219 |
2.19 |
Fortuna |
Ag
(g/t) |
964 |
0 |
2,630 |
127 |
204 |
1.60 |
Au
(g/t) |
964 |
0 |
21.00 |
0.98 |
1.77 |
1.80 |
Pb
(ppm) |
850 |
3 |
667 |
31 |
34 |
1.09 |
Zn
(ppm) |
831 |
24 |
1,052 |
79 |
59 |
0.74 |
Cu
(ppm) |
831 |
4 |
844 |
30 |
33 |
1.12 |
Paloma |
Ag
(g/t) |
261 |
0 |
3,299 |
165 |
407 |
2.47 |
Au
(g/t) |
261 |
0 |
19.95 |
1.35 |
2.77 |
2.06 |
Pb
(ppm) |
224 |
3 |
427 |
28 |
47 |
1.67 |
Zn
(ppm) |
212 |
7 |
461 |
81 |
49 |
0.60 |
Cu
(ppm) |
212 |
1 |
483 |
36 |
47 |
1.29 |
Bonanza
HW splay |
Ag
(g/t) |
925 |
0 |
6,858 |
261 |
576 |
2.20 |
Au
(g/t) |
925 |
0 |
39.34 |
1.95 |
4.32 |
2.21 |
Pb
(ppm) |
884 |
6 |
109,664 |
2,608 |
5,839 |
2.24 |
Zn
(ppm) |
121 |
71 |
39,509 |
3,487 |
6,684 |
1.92 |
Cu
(ppm) |
123 |
9 |
13,603 |
623 |
1,617 |
2.59 |
Trinidad
FW splay |
Ag
(g/t) |
417 |
0 |
1,604 |
104 |
194 |
1.87 |
Au
(g/t) |
417 |
0 |
28.00 |
0.52 |
1.58 |
3.07 |
Pb
(ppm) |
195 |
6 |
4,310 |
301 |
520 |
1.73 |
Zn
(ppm) |
69 |
73 |
5,810 |
817 |
1,226 |
1.50 |
Cu
(ppm) |
69 |
7 |
351 |
60 |
69 |
1.14 |
Trinidad
FW2 splay |
Ag
(g/t) |
3,161 |
0.25 |
5,557 |
123 |
274 |
2.24 |
Au
(g/t) |
3,161 |
0.01 |
30.89 |
0.61 |
1.41 |
2.31 |
Pb
(ppm) |
3,090 |
8 |
18,351 |
395 |
895 |
2.27 |
Zn
(ppm) |
307 |
2 |
16,172 |
607 |
1,212 |
2.00 |
Cu
(ppm) |
307 |
1 |
1,818 |
39 |
108 |
2.77 |
Trinidad
FW3 splay |
Ag
(g/t) |
2,898 |
0 |
15,506 |
234 |
805 |
3.43 |
Au
(g/t) |
2,898 |
0 |
40.06 |
0.91 |
2.22 |
2.44 |
Pb
(ppm) |
2,796 |
4 |
14,028 |
360 |
801 |
2.23 |
Zn
(ppm) |
288 |
39 |
8,537 |
659 |
969 |
1.47 |
|
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
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Vein |
Grade |
Count |
Minimum |
Maximum |
Mean |
SD |
CV |
|
Cu (ppm) |
288 |
3 |
659 |
50 |
56 |
1.11 |
Trinidad
HW splay |
Ag
(g/t) |
227 |
0.25 |
904 |
70 |
127 |
1.83 |
Au
(g/t) |
227 |
0.01 |
11.15 |
0.67 |
1.24 |
1.84 |
Pb
(ppm) |
166 |
4 |
507 |
43 |
50 |
1.16 |
Zn
(ppm) |
66 |
16 |
587 |
95 |
75 |
0.79 |
Cu
(ppm) |
66 |
4 |
56 |
22 |
10 |
0.48 |
Stockwork2 |
Ag
(g/t) |
6,464 |
0 |
10,389 |
230 |
535 |
2.33 |
Au
(g/t) |
6,464 |
0 |
124.78 |
1.30 |
3.45 |
2.65 |
Pb
(ppm) |
6,325 |
5 |
62,390 |
1,130 |
2,550 |
2.26 |
Zn
(ppm) |
780 |
32 |
62,063 |
1,595 |
3,721 |
2.33 |
Cu
(ppm) |
780 |
4 |
4,520 |
108 |
279 |
2.58 |
Stockwork3 |
Ag
(g/t) |
1,565 |
1 |
8,289 |
304 |
662 |
2.17 |
Au
(g/t) |
1,565 |
0 |
40.33 |
1.50 |
3.11 |
2.08 |
Pb
(ppm) |
1,445 |
7 |
27,706 |
1,103 |
1,952 |
1.77 |
Zn
(ppm) |
174 |
39 |
13,244 |
1,213 |
1,949 |
1.61 |
Cu
(ppm) |
174 |
4 |
1,469 |
80 |
141 |
1.76 |
Stockwork4 |
Ag
(g/t) |
179 |
0 |
2,401 |
102 |
295 |
2.89 |
Au
(g/t) |
179 |
0 |
8.71 |
0.40 |
1.04 |
2.59 |
Pb
(ppm) |
117 |
2 |
1,934 |
230 |
372 |
1.62 |
Zn
(ppm) |
74 |
57 |
3,532 |
470 |
671 |
1.43 |
Cu
(ppm) |
74 |
6 |
342 |
40 |
49 |
1.21 |
Victoria
(Vmz) |
Ag
(g/t) |
713 |
0 |
1,879 |
99 |
185 |
1.87 |
Au
(g/t) |
713 |
0 |
20.18 |
0.85 |
1.74 |
2.04 |
Pb
(ppm) |
708 |
3 |
5,611 |
118 |
418 |
3.54 |
Zn
(ppm) |
696 |
8 |
8,410 |
272 |
686 |
2.52 |
Cu
(ppm) |
696 |
2 |
816 |
41 |
72 |
1.76 |
Note: SD = standard
deviation, CV = coefficient of variation.
Exploratory data
analysis of the composites indicates that sub-domaining is not required beyond the domaining described above. However, there are several
east–west-oriented faults cross cutting the mineralized structures that result in some of the mineralized domains being downthrown
to the north. The faults have caused significant movement on the main structures including the Trinidad, Bonanza and Stockwork veins
and these structures have been sub-domained for topcutting, undergone variographic analysis and estimation.
| 14.6.4 | Extreme value treatment |
Top cuts of extreme
grade values prevent over-estimation or smearing in domains due to disproportionately high-grade samples. Whenever the domain contains
an extreme grade value, this extreme grade will overly influence the estimated grades local to it.
If the extreme
values are supported by surrounding data, are a valid part of the sample population, and are not considered to pose a risk to estimation
quality, then they can be left untreated. If the extreme values are considered a valid part of the population but are considered to pose
a risk for estimation quality (e.g., because they are poorly supported by neighboring values), they should be top cut. Top cutting is
the practice of resetting all values above a certain threshold value to the threshold value.
Fortuna examined
the grades of all metals to be estimated including silver, gold, lead, zinc, and copper to identify the presence and nature of extreme
grade values. This was done by examining the sample histogram, log histogram, log-probability plot, and by examining the
December 31, 2023 | Page 120 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
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spatial location of extreme values. Some
of the veins have insufficient composites to allow a confident determination of top cut thresholds. In these cases, a threshold has been
applied that relates to associated vein structures. Top cut thresholds were determined by examination of the same statistical plots and
by examination of the effect of top cuts on the mean, variance, and coefficient of variation of the sample data. Top cut thresholds used
for each vein are shown in Table 14.3.
Table 14.3 Top cut thresholds
by vein
Vein |
Grade |
Top
Cut
Value |
Original
Mean |
Top
Cut Mean |
Difference
(%) |
Bonanza |
Ag
(g/t) |
3,750 |
212 |
209 |
2 |
Au
(g/t) |
31 |
1.90 |
1.84 |
3 |
Pb
(ppm) |
16,000 |
479 |
453 |
6 |
Zn
(ppm) |
17,000 |
394 |
362 |
8 |
Cu
(ppm) |
1,150 |
55 |
50 |
10 |
Bonanza
Sur |
Ag
(g/t) |
100 |
23 |
18 |
23 |
Au
(g/t) |
0.95 |
0.17 |
0.15 |
13 |
Pb
(ppm) |
195 |
148 |
65 |
56 |
Zn
(ppm) |
525 |
310 |
189 |
39 |
Cu
(ppm) |
80 |
53 |
31 |
41 |
Trinidad |
Ag
(g/t) |
4,100 |
204 |
195 |
5 |
Au
(g/t) |
22.5 |
1.16 |
1.10 |
6 |
Pb
(ppm) |
25,000 |
708 |
633 |
11 |
Zn
(ppm) |
23,400 |
1,099 |
834 |
24 |
Cu
(ppm) |
1,670 |
81 |
74 |
10 |
Trinidad
Norte |
Ag
(g/t) |
1,390 |
79 |
71 |
10 |
Au
(g/t) |
8.7 |
0.45 |
0.41 |
8 |
Pb
(ppm) |
4,200 |
324 |
308 |
5 |
Zn
(ppm) |
2,800 |
511 |
385 |
25 |
Cu
(ppm) |
210 |
38 |
31 |
18 |
Stockwork |
Ag
(g/t) |
4,500 |
267 |
260 |
3 |
Au
(g/t) |
46 |
2.34 |
2.19 |
6 |
Pb
(ppm) |
16,300 |
511 |
502 |
2 |
Zn
(ppm) |
12,200 |
715 |
690 |
3 |
Cu
(ppm) |
1,250 |
90 |
86 |
4 |
Stockwork
Norte |
Ag
(g/t) |
5,000 |
342 |
326 |
5 |
Au
(g/t) |
31 |
2.09 |
2.00 |
4 |
Pb
(ppm) |
20,100 |
985 |
966 |
2 |
Zn
(ppm) |
17,300 |
1,346 |
1,306 |
3 |
Cu
(ppm) |
1,550 |
112 |
109 |
3 |
Stockwork
Sur |
Ag
(g/t) |
840 |
137 |
127 |
8 |
Au
(g/t) |
4.75 |
0.89 |
0.77 |
14 |
Pb
(ppm) |
1,170 |
248 |
212 |
15 |
Zn
(ppm) |
1,750 |
561 |
561 |
0 |
Cu
(ppm) |
205 |
56 |
51 |
9 |
Fortuna |
Ag
(g/t) |
1,000 |
127 |
124 |
3 |
Au
(g/t) |
9.15 |
0.98 |
0.94 |
4 |
Pb
(ppm) |
160 |
31 |
30 |
3 |
Zn
(ppm) |
220 |
79 |
76 |
4 |
Cu
(ppm) |
130 |
30 |
28 |
4 |
Paloma |
Ag
(g/t) |
1,250 |
165 |
136 |
18 |
Au
(g/t) |
8.9 |
1.35 |
1.18 |
12 |
Pb
(ppm) |
160 |
28 |
25 |
11 |
Zn
(ppm) |
228 |
81 |
79 |
3 |
|
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Vein |
Grade |
Top
Cut
Value |
Original
Mean |
Top
Cut Mean |
Difference
(%) |
|
Cu
(ppm) |
200 |
36 |
35 |
5 |
Bonanza
HW splay |
Ag
(g/t) |
2,500 |
263 |
246 |
7 |
Au
(g/t) |
19.5 |
1.97 |
1.86 |
6 |
Pb
(ppm) |
24,000 |
2621 |
2448 |
7 |
Zn
(ppm) |
14,000 |
3,541 |
2,804 |
21 |
Cu
(ppm) |
3,515 |
646 |
493 |
24 |
Bonanza
HW splay Sur |
Ag
(g/t) |
43 |
24 |
12 |
48 |
Au
(g/t) |
1 |
0.24 |
0.16 |
34 |
Pb
(ppm) |
1,945 |
933 |
371 |
60 |
Zn
(ppm) |
5,370 |
2,244 |
1,251 |
44 |
Cu
(ppm) |
184 |
89 |
74 |
17 |
Trinidad
FW splay |
Ag
(g/t) |
675 |
103.67 |
93.02 |
10 |
Au
(g/t) |
3.5 |
0.52 |
0.42 |
19 |
Pb
(ppm) |
1,450 |
301 |
266 |
12 |
Zn
(ppm) |
2,850 |
817 |
699 |
14 |
Cu
(ppm) |
185 |
60 |
55 |
10 |
Trinidad
FW2 splay |
Ag
(g/t) |
2,250 |
123 |
119 |
3 |
Au
(g/t) |
8.6 |
0.61 |
0.58 |
5 |
Pb
(ppm) |
6,500 |
395 |
379 |
4 |
Zn
(ppm) |
3,350 |
607 |
544 |
10 |
Cu
(ppm) |
150 |
39 |
32 |
17 |
Trinidad
FW3 splay |
Ag
(g/t) |
3,725 |
234 |
205 |
13 |
Au
(g/t) |
13.9 |
0.91 |
0.86 |
5 |
Pb
(ppm) |
5,800 |
360 |
347 |
4 |
Zn
(ppm) |
3,200 |
659 |
611 |
7 |
Cu
(ppm) |
185 |
50 |
48 |
5 |
Trinidad
HW splay |
Ag
(g/t) |
355 |
70 |
60 |
15 |
Au
(g/t) |
3.5 |
0.67 |
0.60 |
11 |
Pb
(ppm) |
127 |
43 |
40 |
8 |
Zn
(ppm) |
165 |
95 |
86 |
10 |
Cu
(ppm) |
40 |
22 |
21 |
3 |
Stockwork2 |
Ag
(g/t) |
4,650 |
230 |
226 |
2 |
Au
(g/t) |
27.5 |
1.30 |
1.26 |
3 |
Pb
(ppm) |
21,200 |
1,130 |
1,106 |
2 |
Zn
(ppm) |
17,750 |
1,595 |
1,504 |
6 |
Cu
(ppm) |
1,600 |
108 |
101 |
6 |
Stockwork3 |
Ag
(g/t) |
4,600 |
304 |
298 |
2 |
Au
(g/t) |
18 |
1.50 |
1.44 |
4 |
Pb
(ppm) |
11,400 |
1,103 |
1,080 |
2 |
Zn
(ppm) |
5,800 |
1,213 |
1,103 |
9 |
Cu
(ppm) |
260 |
80 |
66 |
18 |
Stockwork4 |
Ag
(g/t) |
425 |
102 |
65 |
37 |
Au
(g/t) |
2.6 |
0.40 |
0.32 |
21 |
Pb
(ppm) |
1,050 |
230 |
211 |
8 |
Zn
(ppm) |
2,200 |
470 |
451 |
4 |
Cu
(ppm) |
145 |
40 |
37 |
8 |
Victoria
(Vmz) |
Ag
(g/t) |
770 |
99 |
93 |
6 |
Au
(g/t) |
6.7 |
0.85 |
0.79 |
7 |
Pb
(ppm) |
1,400 |
118 |
95 |
20 |
Zn
(ppm) |
2,700 |
272 |
239 |
12 |
Cu
(ppm) |
255 |
41 |
37 |
10 |
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The application
of the top cuts does not significantly alter the mean of the sample data in most of the domains with the exception of the Bonanza HW,
Trinidad HW, Trinidad FW, Trinidad FW3, and Stockwork 4 veins. This is because these domains are defined by fewer composites with a small
number (2 to 3) having extreme values far in excess of any other value. Once these composites are reset the effect on the mean is significant,
but likely to be more representative of the domain as a whole.
The estimation
process does not exclude these extreme values from the process completely. Instead, these composites are used, untreated, to estimate
the blocks in a small halo around the identified extreme value. In the case of silver this area of influence is 6 m and for gold 4 m.
This helps to maintain the nugget style of mineralization observed underground. The extreme values are top cut for the estimation of
any blocks beyond these haloes.
| 14.6.5 | Boundary conditions |
Boundary conditions
are known to be abrupt, with underground workings identifying a sharp contact between the mineralized vein structure and the host rock.
Domain boundaries were treated as hard boundaries. Only samples coded within a vein were used to simulate or estimate grades within that
vein, to prevent smearing of high-grade samples in the vein into the low-grade host rock, and vice versa.
| 14.6.6 | Sample type comparison |
A comparison between
drill hole and channel sample types was conducted to assess if any bias exists between the two sampling techniques. Areas in the Trinidad
and Bonanza veins were chosen that displayed a similar spatial coverage for both channel and drill hole samples.
Statistical results
including probability-probability and quantile-quantile plots were examined. Results showed a bias with grades from channel samples reporting
higher values than those from drill hole samples. However, the difference is likely to be partially due to the preferential sampling
in the mineralized domain and was determined to be not significant enough to warrant the removal of the channel samples from the estimation
process.
It was decided
that both sample types were required to provide the best assessment of the deposit with reconciliation results supporting the usage of
channels and drill holes.
It is important
that the relationship between constituents is maintained in each of the realizations produced during simulation. The correlation between
gold and silver grades was investigated for each vein (Table 14.4).
Table
14.4 Correlation coefficients of gold and silver grades by vein
Vein |
Correlation Coefficient |
Bonanza |
0.81 |
Bonanza South |
0.96 |
Trinidad |
0.92 |
Trinidad North |
0.94 |
Stockwork |
0.71 |
Stockwork South |
0.79 |
Stockwork North |
0.94 |
Fortuna |
0.85 |
Paloma |
0.94 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Vein |
Correlation Coefficient |
Bonanza HW |
0.90 |
Trinidad FW |
0.62 |
Trinidad FW2 |
0.97 |
Trinidad FW3 |
0.92 |
Trinidad HW |
0.95 |
Stockwork 2 |
0.86 |
Stockwork 3 |
0.98 |
Stockwork 4 |
0.97 |
Diedro |
0.94 |
Narrow vein1 |
1.00 |
Sk vein 2 |
0.96 |
Sk vein 6 |
1.00 |
Victoria |
0.90 |
Victoria HW1 |
0.96 |
Victoria HW2 |
0.95 |
Victoria HW3 |
0.98 |
A strong positive
correlation exists between gold and silver composite grades in each of the domains. The correlation statistics are reinforced by examining
scatterplots of silver and gold grades for the different veins where a strong positive relationship is displayed.
It is expected
that similar correlation coefficients and positive grade relationships are present in the realizations to ensure reasonable silver equivalent
grades are estimated. These correlations have been tested as part of the validation process as described in Section 14.9.
| 14.6.8 | Continuity
analysis |
Continuity analysis
refers to the analysis of the spatial correlation between sample pairs to determine the major axis of spatial continuity.
Horizontal, across
strike, and down dip continuity maps were examined (and their underlying variograms) for silver and gold to determine the directions
of greatest and least continuity. As each vein has a distinct strike and dip direction analysis was only required to ascertain if a plunge
direction was present.
Continuity maps
of the dip plane were examined to ascertain if a plunge was present in any of the veins. The presence of several faults cross cutting
perpendicular to the mineralization down throwing blocks to the north can lead to a false plunge, but when this movement is accounted
for the presence of a distinctive plunge in the grade continuity could not be established for any of the veins and therefore variograms
are generally modeled along strike and down dip.
Variograms were
modelled for the major, semi-major, and minor axes. This exercise creates a mathematical model of the spatial variance that can be used
for kriging the grades into the block model. Grades were transformed to a normal distribution using polynomials (normal score) and the
modeled variograms back-transformed to represent the variability of the actual grades.
The most important
aspects of the variogram model are the nugget and the short-range characteristics. These aspects have the most influence on the simulation
of grade. The nugget effect is the variance between sample pairs at the same location (zero distance). Nugget effect contains components
of inherent variability, sampling error, and analytical
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Technical Report |
error.
A high nugget effect implies that there is a high degree of randomness in the sample grades (i.e., samples taken even at the same location
can have very different grades). The best technique for determining the nugget effect is to examine the downhole variogram calculated
with lags equal to the composite length.
After determining
the nugget effect, the next step is to model directional variograms in the three principal directions based on the directions chosen
from the continuity maps. It was not always possible to produce a variogram for the minor axes, and in these cases the ranges for the
minor axes were taken from the downhole variograms, which have a similar orientation (perpendicular to the vein) as the minor axes.
Variogram
parameters for each vein are detailed in Table 14.5. Continuity analysis and variogram modelling were conducted in Supervisor version
8. The parameters reported are back-transformed from normal scored modelled variograms and correspond with the heterogeneous nature of
the mineralization.
Table
14.5 Variogram model normal score parameters
Vein |
Metal |
Major
Axis
Orientation |
C0§ |
C1§ |
Ranges
(m)† |
C2§ |
Ranges
(m)† |
C3§ |
Ranges
(m)† |
|
Bonanza
|
Ag |
75°
® 260° |
0.10 |
0.62 |
9,9,4 |
0.20 |
33,29,35 |
0.08 |
289,232,52 |
|
Au |
75°
® 260° |
0.10 |
0.61 |
9,9,5 |
0.20 |
33,29,30 |
0.09 |
303,260,41 |
|
Trinidad |
Ag |
00°
® 355° |
0.25 |
0.50 |
14,7,5 |
0.15 |
49,42,14 |
0.10 |
351,92,17 |
|
Au |
00°
® 355° |
0.20 |
0.59 |
14,8,3 |
0.13 |
54,42,9 |
0.08 |
356,105,11 |
|
Stockwork |
Ag |
00°
® 340° |
0.17 |
0.53 |
8,4,5 |
0.20 |
35,29,9 |
0.12 |
161,58,12 |
|
Au |
00°
® 340° |
0.16 |
0.55 |
8,6,4 |
0.20 |
37,27,10 |
0.10 |
125,64,12 |
|
Stockwork
2 |
Ag |
80°
® 250° |
0.15 |
0.68 |
15,8,8 |
0.14 |
36,36,14 |
0.03 |
131,124,17 |
|
Au |
80°
® 250° |
0.19 |
0.65 |
15,7,8 |
0.11 |
32,31,12 |
0.05 |
79,74,20 |
|
Fortuna |
Ag |
00°
® 355° |
0.27 |
0.48 |
9,13,5 |
0.24 |
95,20,10 |
|
|
|
Au |
00°
® 355° |
0.12 |
0.50 |
31,13,5 |
0.38 |
138,44,23 |
|
|
|
Paloma
|
Ag |
10°
® 344° |
0.12 |
0.49 |
6,8,5 |
0.37 |
17,23,10 |
0.02 |
110,65,15 |
|
Au |
10°
® 344° |
0.21 |
0.36 |
4,31,5 |
0.12 |
43,51,10 |
0.10 |
94,65,15 |
|
Bonanza
HW |
Ag |
00°
® 325° |
0.05 |
0.71 |
12,18,5 |
0.24 |
73,49,15 |
|
|
|
Au |
00°
® 325° |
0.08 |
0.69 |
13,11,5 |
0.23 |
82,54,15 |
|
|
|
Trinidad
FW |
Ag |
80°
® 260° |
0.48 |
0.18 |
13,4,5 |
0.15 |
65,11,12 |
0.18 |
82,38,18 |
|
Au |
80°
® 260° |
0.55 |
0.26 |
30,5,5 |
0.13 |
50,14,10 |
0.06 |
61,37,16 |
|
Trinidad
FW2 |
Ag |
00°
® 355° |
0.29 |
0.48 |
10,7,10 |
0.20 |
32,43,30 |
0.03 |
75,86,36 |
|
Au |
00°
® 355° |
0.28 |
0.44 |
8,5,15 |
0.21 |
27,27,19 |
0.07 |
92,78,31 |
|
Trinidad
FW3 |
Ag |
75°
® 245° |
0.18 |
0.53 |
7,9,5 |
0.29 |
71,45,20 |
|
|
|
Au |
75°
® 245° |
0.13 |
0.60 |
13,10,5 |
0.28 |
68,48,21 |
|
|
|
Trinidad
HW |
Ag |
00°
® 350° |
0.21 |
0.48 |
4,17,5 |
0.19 |
26,63,10 |
0.12 |
85,73,15 |
|
Au |
75°
® 260° |
0.18 |
0.39 |
13,5,5 |
0.25 |
47,21,8 |
0.18 |
57,26,12 |
|
Stockwork
3 |
Ag |
80°
® 250° |
0.18 |
0.47 |
11,14,12 |
0.23 |
71,28,17 |
0.12 |
105,35,21 |
|
Au |
80°
® 250° |
0.16 |
0.35 |
5,7,9 |
0.18 |
28,20,12 |
0.31 |
78,32,19 |
|
Stockwork
4 |
Ag |
00°
® 340° |
0.17 |
0.53 |
8,4,5 |
0.20 |
35,29,9 |
0.12 |
161,58,12 |
|
Au |
00°
® 340° |
0.16 |
0.55 |
8,6,4 |
0.20 |
37,27,10 |
0.10 |
125,64,12 |
|
Diedro
Vein 2 |
Ag |
00°
® 330° |
0.26 |
0.44 |
41,18,5 |
0.30 |
102,48,10 |
|
|
|
Au |
00°
® 330° |
0.31 |
0.45 |
5,26,5 |
0.10 |
40,92,8 |
0.14 |
115,100,10 |
|
Victoria
Mz |
Ag |
00°
® 335° |
0.22 |
0.42 |
37,34,5 |
0.26 |
287,115,10 |
0.10 |
329,219,15 |
|
Au |
00°
® 335° |
0.19 |
0.30 |
32,29,5 |
0.28 |
36,64,10 |
0.23 |
251,193,15 |
|
Victoria
|
Ag |
20°
® 164° |
0.17 |
0.52 |
49,73,5 |
0.31 |
92,87,10 |
|
|
|
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Vein |
Metal |
Major
Axis
Orientation |
C0§ |
C1§ |
Ranges
(m)† |
C2§ |
Ranges
(m)† |
C3§ |
Ranges
(m)† |
|
HW1/2/3 |
Au |
20°
® 164° |
0.15 |
0.58 |
47,62,5 |
0.27 |
76,71,10 |
|
|
|
Narrow
Vein 1 |
Ag |
40°
® 160° |
0.12 |
0.73 |
28,30,4 |
0.15 |
75,52,7 |
|
|
|
Au |
40°
® 160° |
0.22 |
0.45 |
26,30,5 |
0.33 |
70,53,9 |
|
|
|
SK
02 |
Ag |
00°
® 350° |
0.29 |
0.39 |
12,17,5 |
0.32 |
40,30,10 |
|
|
|
Au |
00°
® 350° |
0.13 |
0.54 |
16,18,5 |
0.33 |
36,35,10 |
|
|
|
SK
03 |
Ag |
75°
® 260° |
0.10 |
0.62 |
9,9,4 |
0.20 |
33,29,35 |
0.08 |
289,232,52 |
|
Au |
75°
® 260° |
0.10 |
0.61 |
9,9,5 |
0.20 |
33,29,30 |
0.09 |
303,260,41 |
|
SK
06 |
Ag |
00°
® 325° |
0.05 |
0.71 |
12,18,5 |
0.24 |
73,49,15 |
|
|
|
Au |
00°
® 325° |
0.08 |
0.69 |
13,11,5 |
0.23 |
82,54,15 |
|
|
|
Note:
§ variances have been normalised to a total of one; † ranges for major, semi-major, and minor axes, respectively; structures
are modelled with a spherical model |
|
|
14.6.10 | Opinion
on the quality of the modeled variograms |
Modeling
of variograms can be somewhat of a subjective process depending on the quality of the experimental variograms. Confidence in the modeled
variograms for the Bonanza, Trinidad, Stockwork, and Stockwork2 domains is high due to the clearly-defined continuity displayed by the
experimental variograms. Confidence in the modelled variograms for the Fortuna, Trinidad FW2, Trinidad FW3, Stockwork3 and Victoria Mz
domains is moderate to low for all other veins due to the lower composite numbers, and this is reflected in their classification. The
veins with low confidence do not represent a significant component of the San Jose Mineral Resource estimate.
| 14.6.11 | Selective
mining unit |
An appropriate
selective mining unit (SMU) was chosen based on reconciliation results and the equipment used for extraction underground. An appropriate
SMU has been determined to be 2 m x 2 m x 2 m based on the application of new mining equipment to exploit areas of narrow mineralization.
Block model
parameters used for compiling the San Jose deposit models containing all vein information are detailed in Table 14.6.
Table
14.6 Block model parameters
Deposit |
Direction |
Model
Origin |
SMU
Block
Size (m) |
No. of
Blocks |
Trinidad |
Easting |
744960 |
2 |
280 |
Northing |
1846396 |
2 |
736 |
Elevation |
720 |
2 |
422 |
Victoria |
Easting |
744832 |
2 |
392 |
Northing |
1847400 |
2 |
750 |
Elevation |
696 |
2 |
348 |
Vein geometry
was considered in the block modeling process. The narrow and undulating nature of the veins means that an entire block is often not spatially
located within the vein wireframe. The model was subcelled so that the geometry of the vein was fully represented in the block model.
A second model where only full block sizes are presented included a field that recorded the proportion of the block that was located
inside the vein wireframe. To ensure the volumes were accurately represented a volume comparison between the wireframe, subcelled and
parent block model proportions was conducted to validate the process.
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The sample
data and the blocks were categorized into their mineralized domains for estimation (Section 14.5). The sample data were composited
(Section 14.6.1) and, where necessary, top cut prior to estimation (Section 14.6.4). All veins were estimated by ordinary kriging
(OK). Block size selection corresponded to an SMU size of 2 m x 2 m x 2 m. Each block was discretized into three points
along strike, by three points down dip, by three points across strike and grade interpolated into parent cells. The following search
neighborhood was used for estimation of silver and gold based on 80 % of the grade variance as indicated by the variograms:
| · | Search
range of approximately 25 to 30 m along strike and down dip and 10 m across the
vein. |
| · | Minimum
of 4 composites per estimate. |
| · | Maximum
of 24 composites per estimate. |
| · | Maximum
of 2 composites per drill hole or channel. |
To maintain
the variability that is observed across the vein structures from hanging wall to footwall in wider veins, estimation was conducted using
up to four bands where blocks and samples were identified, and estimation was restricted to within each individual band. This ensured
estimation dynamically followed the orientation of the vein structure along strike and down dip. A multiple of the search neighborhood
was employed, to ensure the estimation of all blocks, with a second pass that was twice the original search range size, and a third pass
six times the original size. The number of composites and drill holes used in the estimate were taken into account during classification,
as described in Section 14.11. The percentage of blocks estimated using the first or second passes represents more than 97 % of
the total reported Mineral Resources and more than 99 % of those classified as Measured or Indicated.
There are
a total of 5,602 drill core density measurements that were taken by Cuzcatlan of which 50 (<1%) were discarded as being outliers resulting
in 5,552 values of which 2,231 are located in vein domains estimated as of June 30, 2023 (Table 14.7). A total of 1,105 density
measurements were also taken from underground workings but the results differ significantly from those observed in the drill core and
were discarded.
Table
14.7 Density statistics by vein
Vein |
No. of
samples |
Mean
(t/m3) |
Min.
(t/m3) |
Max.
(t/m3) |
Std.
Dev. |
|
Bonanza |
453 |
2.60 |
2.32 |
2.77 |
0.07 |
|
Trinidad |
388 |
2.59 |
2.33 |
2.78 |
0.08 |
|
Stockwork |
686 |
2.60 |
2.39 |
2.84 |
0.06 |
|
Fortuna |
68 |
2.49 |
2.31 |
2.67 |
0.09 |
|
Paloma |
10 |
2.58 |
2.43 |
2.67 |
0.08 |
|
Bonanza
HW |
25 |
2.64 |
2.55 |
2.89 |
0.09 |
|
Trinidad
FW |
4 |
2.68 |
2.64 |
2.76 |
0.05 |
|
Trinidad
FW2 |
87 |
2.58 |
2.46 |
2.70 |
0.05 |
|
Trinidad
FW3 |
80 |
2.59 |
2.50 |
2.69 |
0.04 |
|
Trinidad
HW |
8 |
2.63 |
2.62 |
2.64 |
0.01 |
|
Stockwork2 |
151 |
2.61 |
2.48 |
2.77 |
0.06 |
|
Stockwork3 |
37 |
2.58 |
2.45 |
2.81 |
0.08 |
|
Stockwork4 |
9 |
2.59 |
2.55 |
2.63 |
0.03 |
|
SK2 |
17 |
2.61 |
2.54 |
2.71 |
0.05 |
|
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Vein |
No. of
samples |
Mean
(t/m3) |
Min.
(t/m3) |
Max.
(t/m3) |
Std.
Dev. |
|
SK3 |
10 |
2.59 |
2.52 |
2.67 |
0.05 |
|
Narrow
vein 1 |
10 |
2.60 |
2.54 |
2.67 |
0.04 |
|
Diedro
vein 2 |
39 |
2.55 |
2.38 |
2.73 |
0.08 |
|
Sub-total
- Trinidad |
2,082 |
2.59 |
2.31 |
2.89 |
0.07 |
|
Victoria
(Vmz) |
96 |
2.55 |
2.37 |
2.69 |
0.08 |
|
Victoria
(Vhwz1) |
22 |
2.57 |
2.47 |
2.70 |
0.06 |
|
Victoria
(Vhwz2) |
20 |
2.55 |
2.44 |
2.68 |
0.07 |
|
Victoria
(Vhwz3) |
11 |
2.56 |
2.50 |
2.64 |
0.05 |
|
Sub-total
- Victoria |
149 |
2.59 |
2.37 |
2.70 |
0.08 |
|
Non-vein |
3,172 |
2.58 |
2.18 |
3.19 |
0.08 |
|
Samples
of vein material are dominated by measurements taken from the Bonanza, Trinidad, Stockwork and Stockwork2 domains, comprising 1,678 of
the 2,082 Trinidad deposit total measurements. The spatial coverage of density measurements in these four veins meant that bulk density
values could be estimated into the block model using ordinary kriging.
For veins
not estimated, if more than 30 density measurements had been collected the mean density for that vein was assigned (Fortuna, Stockwork
3, Trinidad FW2, Trinidad FW3, and Victoria main). If less than 30 measurements had been obtained a set density value equivalent of the
global mean of 2.59 g/cm3 for Trinidad veins and 2.55 g/cm3 was assigned based on the above statistics and reconciliation
results.
| 14.9 | Estimation
validation |
Validation
of the silver, gold, lead, zinc, and copper grade estimates was undertaken using the following methods:
| · | Global
comparison of the estimated grades with an inverse distance weighting power of 2 (IDW) estimate. |
| · | Local
comparison of the estimated grades with the input data using swath plots. |
| · | A
visual comparison of the estimated models with the input data to ensure sensible orientations
of continuity and sensible grade distributions. |
| · | Reconciliation
of block model estimates versus actual operational results. |
Global
validation of the estimate involves comparing the mean OK grade for each vein against the mean declustered grade generated using the
IDW estimation approach. Analysis was performed by classification to ensure low confidence areas do not distort the results from higher
confidence regions (Table 14.8). The results are regarded as reasonable, with differences being less than 10 %.
Table
14.8 Global estimation validation
Classification |
OK |
IDW |
Diff
(OK v IDW) |
Ag
(g/t) |
Au
(g/t) |
Ag
(g/t) |
Au
(g/t) |
Ag |
Au |
Measured |
158 |
1.01 |
152 |
1.01 |
4% |
4% |
Indicated |
96 |
0.65 |
90 |
0.60 |
7% |
8% |
Inferred |
65 |
0.47 |
60 |
0.44 |
8% |
6% |
Global |
92 |
0.62 |
86 |
0.58 |
6% |
7% |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
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Slice validation
plots of estimated block grades and declustered input sample grades were generated for each of the veins along strike and down dip to
validate the estimates on a local scale. Validation of the local estimates assesses each model to ensure over-smoothing or conditional
bias is not being introduced by the estimation process and an acceptable level of grade variation is present. An example slice (or swath)
plot for Stockwork domain is displayed in Figure 14.3.
Figure
14.3 Swath plot for gold grades in the Stockwork vein
Figure
prepared by Cuzcatlan, 2023
December 31, 2023 | Page 129 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
The slice
plots display a good continuity between the OK, IDW, and nearest neighbor (NN) estimates, as well as the declustered composites
indicating the OK estimates are not over-smoothed. Based on the results it was concluded that OK was a suitable interpolation method
providing reasonable global and local estimates.
Validation
of each of the metals was completed by comparing the estimated block model grades to the composite grades used in the estimation. Checks
were performed by generating long sectional views (Figure 14.4) as well as checking cross sectional views along the full strike length
of each vein.
Figure
14.4 Visual validation of estimated block grades versus composites – Stockwork vein
Figure
prepared by Cuzcatlan, 2023
The sections
displayed a good visual correlation between the input composite grades and the output block model grades accounting for the expected
level of smoothing due to the volume: variance relationship.
| 14.9.4 | Mine
reconciliation |
The ultimate
validation of the block model is to compare actual grades to predicted grades using the established estimation parameters. A comparison
of the estimation against mineral in-situ (SMU blocks estimated as being above cut-off grade during extraction) is conducted monthly
as part of the ongoing reconciliation program and demonstrates a good level of correlation with tonnes and grade generally within 10
% on a quarterly basis. Gold grades tend to be more erratic than other metals and the operation reported lower than expected grades for
the first half of 2023. Adjustments have been made in the estimation process to address this over-estimation issue.
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| 14.10 | Mineral
Resource depletion |
All underground
development and stopes at the San Jose Mine are regularly surveyed using total station methods as a component of monitoring the underground
workings. The survey information is imported into Datamine and used to generate 3D solids defining the extracted regions of the mine.
Each wireframe is assigned a date corresponding to when the material was extracted, providing Cuzcatlan a detailed history of the progression
of mining.
The 3D
solids were used to identify resource blocks that have been extracted and assign a code that corresponded to the date of extraction in
the resource block model.
Removal
of extracted material often results in remnant resource blocks being left in the model that will likely never be exploited. These represent
inevitable components of mining such as pillars and sills, or lower-grade peripheral material that was left behind. To take this into
account, areas were identified by the mine planning department as being fully exploited, and any remnant blocks within these areas were
identified in the block model using the code “RM = 1” and excluded from the reported Mineral Resources.
| 14.11 | Mineral
Resource classification |
Resource
confidence classification considers a number of aspects affecting confidence in the resource estimation, such as:
| · | Geological
continuity (including geological understanding and complexity). |
| · | Data
density and orientation. |
| · | Data
accuracy and precision. |
| · | Grade
continuity (including spatial continuity of mineralization). |
| · | Simulated
grade variability. |
| 14.11.1 | Geological
continuity |
There is
substantial geological information to support a good understanding of the geological continuity of the primary veins at the San Jose
Mine. Exploration and definition drilling conducted on an approximate 25 m x 25 m grid has supported the geological continuity of the
Bonanza, Trinidad, and Stockwork veins along strike and down dip. Three dimensional models of lithology, alteration, structures and mineralization
have been generated to aid the estimation process.
Understanding
of the vein systems is greatly increased by the presence of extensive underground workings allowing detailed mapping of the geology.
Underground observations have increased the ability to accurately model mineralization. The proximity of resources to underground workings
has been taken into account during resource classification.
Confidence
in the geological continuity of the secondary veins is lower as there tends to be fewer intercepts. The uncertainty in the geology of
the secondary veins has been taken into account during classification.
| 14.11.2 | Data
density and orientation |
The estimation
relies on two types of data, channel samples and drill holes. Cuzcatlan has explored and defined the primary veins using a drilling pattern
spaced roughly 25 to 50 m
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apart along
strike and down dip. Each hole attempts to intercept the vein perpendicular to the strike of mineralization but this is rarely the case,
with the intercept angle being generally between 60 to 90 degrees.
In the
primary veins, exploration drilling data is supported by underground information including channel samples taken at approximately 3 m
intervals along the strike of the mineralization. Geological confidence and estimation quality are closely related to data density, and
this is reflected in the classification.
| 14.11.3 | Data
accuracy and precision |
Classification
of resource confidence is also influenced by the accuracy and precision of the available data. The accuracy and the precision of the
data is determined through QAQC programs and through an analysis of the methods used to measure the data.
All exploration
drill core is sent to ALS Global for sample preparation and analysis. Channel and infill samples were sent to both the ALS Global and
Cuzcatlan laboratories for preparation and analysis prior to February 24, 2012. After this date, underground channel samples have
been sent to the Cuzcatlan Laboratory and ALS Global has been used as an umpire laboratory for duplicate assay purposes. The Cuzcatlan
Laboratory has been ISO certified since March 3, 2018, for sample preparation and assaying of silver and gold.
Quality
control results from the Cuzcatlan Laboratory and the ALS Global laboratory indicate reasonable levels of accuracy with no material issues
of sample switching or contamination. Precision levels for field duplicates are lower than what would normally be regarded as acceptable
and this is partially due to the variable ‘nuggety’ nature of the mineralization (particularly for gold), and partially due
to poor selection of samples for evaluation. When a representative range of grades is assessed, the results are regarded as acceptable.
The QC results indicate that grades reported from both laboratories are suitable for Mineral Resource estimation.
| 14.11.4 | Spatial
grade continuity |
Spatial
grade continuity, as indicated by the variogram, is an important consideration when assigning resource confidence classification. Confidence
in the variogram characteristics, such as the nugget variance and ranges, strongly influence estimation quality parameters.
The variogram
structures for the Bonanza, Bonanza HW, Trinidad, Trinidad FW2, Trinidad FW3, Fortuna, Stockwork, Stockwork2, Stockwork3 and Victoria
main structure veins are well defined and there is a higher level of confidence in these modeled variograms. The structures are not as
well defined in the other veins and some interpretation has been exercised during modeling.
The nugget
effect and short-range variance characteristics of the variogram are the most important measures of continuity. In the primary veins
the back-transformed variogram nugget effect for silver and gold is between 10 % and 30 % of the total variance. Caution should be exercised
in relying on estimated grades representing small volumes due to the grade variability with results being more likely to be representative
over larger volumes (e.g. monthly or quarterly estimates).
Ranges
(the distance at which continuity between sample grades is no longer present) are approximately 30–40 m down dip and along strike.
These distances are typical for epithermal style mineralization and suggest that a drilling grid of 25 m is reasonable for representative
grade simulation in these veins.
December 31, 2023 | Page 132 of 208 |
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
The Mineral
Resource confidence classification of the San Jose Mineral Resource models incorporate the confidence in the drill hole and channel data,
the geological interpretation, geological continuity, data density and orientation, spatial grade continuity, and estimation quality.
The Mineral Resource models were coded as Inferred, Indicated, and Measured in accordance with the 2014 CIM Definition Standards.
Classification was based on the following steps:
| · | Blocks
were considered as Measured Mineral Resources if on average a minimum of 12 composites, from
at least three different channels/drill holes were used in the estimate with the nearest
sample being within 20 % of the variogram range (Bonanza <10 m, Trinidad <12 m, Stockwork
<12 m, and Fortuna <13 m). |
| · | Blocks
were considered as Indicated Mineral Resources if on average a minimum of 10 composites,
from at least two different channels/drill holes were used in the estimate with the nearest
sample being within 40 % of the variogram range (Bonanza <20 m, Trinidad <25 m, Stockwork
<25 m, and Fortuna <26 m). |
| · | Blocks
were considered as Inferred Mineral Resources if a minimum of one composite was used in the
estimate with the nearest sample being within 100 % of the variogram range (Bonanza <50
m, Trinidad <60 m, Stockwork <60 m, and Fortuna <65 m). Only interpolated blocks
(between drill hole or channel intercepts) were classified as Inferred with extrapolated
blocks removed from reporting meaning that the majority of Inferred Mineral Resources are
informed from two or more drill holes. |
| · | Perimeter
strings were digitized in Studio RM and the block model coded as either CLASS=1 (Measured),
CLASS=2 (Indicated) or CLASS =3 (Inferred) based on the above steps to ensure a gradational
effect in the classification. |
The above
criteria ensure a gradation in confidence from Measured to Indicated to Inferred Mineral Resource blocks. It also ensures that blocks
considered as Measured Mineral Resources are informed from at least three sides, blocks considered as Indicated Mineral Resources from
two sides, and blocks considered as Inferred Mineral Resources from one side. Kriging efficiency and the slope of regression were also
used to determine the reasonableness of the above criteria. An example of a classified vein is provided in Figure 14.5 with the selection
criteria used in the categorization.
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Silver Mines Inc.: San Jose Mine, Oaxaca, Mexico
Technical Report |
Figure
14.5 Long section of Stockwork vein displaying Mineral Resource categorization criteria
Figure
prepared by Cuzcatlan, 2023
Notes:
-
Blocks inside green perimeter classified as Measured Mineral Resources
-
Blocks inside orange perimeter classified as Indicated Mineral Resources
-
Blocks inside red perimeter classified as Inferred Mineral Resources
-
White markers represent composites intersecting the Bonanza vein
| 14.12 | Mineral
Resource reporting |
| 14.12.1 | Reasonable
prospects for eventual economic extraction |
Mineral
Resources are reported based on underground mining within mineable stope shapes based on actual operational costs and mining equipment
sizes using silver equivalent grades in the block model calculated based on the projected long-term metal prices and actual metallurgical
recoveries experienced in the plant using the following formula:
Ag Eq
(g/t) = Ag (g/t) + (Au (g/t)*((1,880/23.90)*(91/90)).
Mineral
Resources are reported above a cut-off grade of 130 g/t Ag Eq based on operating costs of US$ 84.94/t comprised of US$ 38.31/t for mining,
US$ 20.71/t for plant, and US$ 25.92 for all other costs including general services and administration, distribution, community
and social relations.
Mineral
Resources identified as being isolated or economically unviable using the floating stope optimizer are excluded from being reported.
| 14.12.2 | Mineral
Resource statement |
Eric Chapman
P. Geo. is the QP for the Mineral Resource estimate for the San Jose Mine. Mineral Resources are reported insitu and have an effective
date of December 31, 2023. Mineral Resources are summarized in Table 14.9. Mineral Resources are estimated by ordinary kriging and
reported within mineable stope shapes accounting for operational
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dilution at the SMU size using a 130 g/t Ag Eq cut-off grade in areas identified
as accessible for underground mining. The Measured and Indicated Mineral Resources are exclusive of those Mineral Resources modified to
produce the Mineral Reserves through the process described in Section 15. Mineral Resources that are not Mineral Reserves do not
have demonstrated economic viability.
Table 14.9
Mineral Resources exclusive of Mineral Reserves reported as of December 31, 2023
Category |
Tonnes (000) |
Ag
(g/t) |
Au
(g/t) |
Ag Eq
(g/t) |
Contained Metal |
Ag (Moz) |
Au (koz) |
Ag Eq (Moz) |
Measured |
45 |
141 |
1.09 |
222 |
0.2 |
2 |
0.3 |
Indicated |
1,001 |
148 |
1.11 |
234 |
4.7 |
36 |
7.5 |
Measured + Indicated |
1,046 |
147 |
1.11 |
234 |
5.0 |
37 |
7.9 |
Inferred |
1,029 |
147 |
1.04 |
229 |
4.9 |
35 |
7.6 |
Notes on Mineral Resources
| · | Mineral Resources are reported insitu, as defined
by the 2014 CIM Definition Standards for Mineral Resources and Mineral Reserves. |
| · | Mineral Resources are reported as of December 31,
2023. |
| · | Mr. Eric Chapman P. Geo., a Fortuna employee,
is the Qualified Person for the estimate. |
| · | Mineral Resources are reported exclusive of Mineral
Reserves. |
| · | Mineral Resources that are not Mineral Reserves
do not have demonstrated economic viability. |
| · | Mineral Resources are reported based on underground
mining within optimized stope designs using a cut-off grade of 130 g/t Ag Eq based on assumed metal prices of US$ 23.90/oz Ag and US$ 1,880/oz
Au, estimated metallurgical recovery rates of 91 % for Ag and 90 % for Au (Ag Eq (g/t) = Ag (g/t) + (Au (g/t)*((1,880/23.90)*(91/90)),
and an operating cost of US$ 84.94/t. |
| · | Mineral Resource tonnes are rounded to the nearest
thousand. |
| · | Totals may not add due to rounding. |
| · | Mineral Resources in this table are not additive
to the Mineral Resources reported in Table 14.10 and Table 14.11. |
Factors that may affect the estimates include:
metal price and exchange rate assumptions; changes to the assumptions used to generate the cut-off grade; changes in local interpretations
of mineralization geometry and continuity of mineralized zones; changes to geological and mineralization shape and geological and grade
continuity assumptions; variations in density and domain assignments; geometallurgical assumptions; changes to geotechnical, mining, dilution,
and metallurgical recovery assumptions; change to the input and design parameter assumptions that pertain to the conceptual stope designs
constraining the estimates; and assumptions as to the continued ability to access the site, retain mineral and surface rights titles,
maintain environment and other regulatory permits, and maintain the social license to operate.
| 14.12.3 | Mineral Resources by key geologic attributes |
The following section
provides a breakdown of the resource estimates based on various key geological attributes. The Mineral Resources presented in this
subsection are not additive to the Mineral Resources presented in Table 14.9. A cornerstone of this analysis involves the evaluation of
the Mineral Resources inclusive of Mineral Reserves for the San Jose Mine, as summarized in Table 14.10. Mineral Resources are reported
within mineable stope shapes and therefore include operational dilution using a 130 g/t Ag Eq cut-off grade as described above.
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Table 14.10
Mineral Resources inclusive of Mineral Reserves reported as of December 31, 2023
Category |
Tonnes (000) |
Ag
(g/t) |
Au
(g/t) |
Ag Eq
(g/t) |
Contained Metal |
Ag (Moz) |
Au (koz) |
Ag Eq (Moz) |
Measured |
154 |
191 |
1.41 |
301 |
0.9 |
7 |
1.5 |
Indicated |
1,828 |
168 |
1.16 |
258 |
9.9 |
68 |
15.2 |
Measured + Indicated |
1,982 |
170 |
1.18 |
262 |
10.8 |
75 |
16.7 |
Inferred |
1,029 |
147 |
1.04 |
229 |
4.9 |
35 |
7.6 |
Notes on Mineral Resources
| · | Mineral Resources are reported insitu as defined
by the 2014 CIM Definition Standards for Mineral Resources and Mineral Reserves. |
| · | Mineral Resources are reported as of December 31,
2023. |
| · | Mr. Eric Chapman P. Geo., a Fortuna employee,
is the Qualified Person for the estimate. |
| · | Mineral Resources are reported inclusive of Mineral
Reserves. |
| · | Mineral Resources that are not Mineral Reserves
do not have demonstrated economic viability. |
| · | Mineral Resources are reported based on underground
mining within optimized stope designs using a cut-off grade of 130 g/t Ag Eq based on assumed metal prices of US$ 23.90/oz Ag and US$
1,880/oz Au, estimated metallurgical recovery rates of 91 % for Ag and 90 % for Au (Ag Eq (g/t) = Ag (g/t) + (Au (g/t)*((1,840/24.15)*(91/90)),
and an operating cost of US$ 84.94/t. |
| · | Mineral Resource tonnes are rounded to the nearest
thousand. |
| · | Totals may not add due to rounding. |
| · | This table is not additive to Table 14.9 or Table
14.11. |
The Mineral Resources can be further assessed
by examining the tonnes and grade associated with each vein at the reported cut-off grade (Table 14.11).
Table 14.11
Mineral Resources inclusive of Mineral Reserves by vein reported as of December 31, 2023
Category |
Vein |
Tonnes
(000) |
Ag
(g/t) |
Au
(g/t) |
Ag Eq
(g/t) |
Contained Metal |
Average
Thickness (m)* |
Ag (koz) |
Au (koz) |
Ag Eq (koz) |
Measured |
Bonanza |
50 |
196 |
1.38 |
303 |
315 |
2.2 |
488 |
9.1 |
Trinidad |
16 |
163 |
1.19 |
256 |
86 |
0.6 |
135 |
5.5 |
Fortuna |
46 |
147 |
1.42 |
258 |
218 |
2.1 |
381 |
10.6 |
Stockwork |
29 |
248 |
1.71 |
381 |
228 |
1.6 |
351 |
12.2 |
Stockwork2 |
13 |
231 |
1.12 |
318 |
95 |
0.5 |
131 |
9.0 |
Total |
154 |
191 |
1.41 |
301 |
941 |
7.0 |
1,486 |
9.7 |
Indicated |
Bonanza |
265 |
175 |
1.26 |
273 |
1,488 |
10.7 |
2,326 |
5.9 |
Bonanza HW |
34 |
226 |
1.77 |
363 |
243 |
1.9 |
392 |
4.2 |
Trinidad |
361 |
132 |
0.81 |
196 |
1,539 |
9.4 |
2,272 |
8.0 |
Trinidad FW |
2 |
118 |
0.60 |
165 |
9 |
0.0 |
12 |
3.0 |
Trinidad FW2 |
55 |
118 |
0.60 |
165 |
241 |
1.2 |
334 |
8.9 |
Trinidad FW3 |
137 |
206 |
0.92 |
278 |
904 |
4.1 |
1,221 |
5.8 |
Paloma |
6 |
174 |
1.47 |
289 |
36 |
0.3 |
60 |
2.8 |
Fortuna |
161 |
138 |
0.85 |
204 |
714 |
4.4 |
1,056 |
7.5 |
Stockwork |
214 |
198 |
1.47 |
313 |
1,362 |
10.1 |
2,148 |
8.6 |
Stockwork2 |
28 |
244 |
1.30 |
346 |
217 |
1.2 |
307 |
5.8 |
Stockwork3 |
22 |
231 |
1.02 |
311 |
167 |
0.7 |
224 |
5.3 |
Victoria (Vmz) |
543 |
169 |
1.38 |
277 |
2,956 |
24.1 |
4,837 |
5.6 |
Total |
1,828 |
168 |
1.16 |
258 |
9,874 |
68.1 |
15,189 |
6.7 |
Inferred |
Bonanza |
59 |
277 |
1.54 |
397 |
526 |
2.9 |
754 |
2.6 |
Bonanza HW |
25 |
100 |
1.10 |
186 |
79 |
0.9 |
147 |
4.2 |
Trinidad |
108 |
105 |
0.73 |
162 |
363 |
2.5 |
561 |
10.6 |
Trinidad FW |
4 |
111 |
0.46 |
147 |
16 |
0.1 |
21 |
3.7 |
Trinidad FW2 |
21 |
121 |
0.58 |
165 |
80 |
0.4 |
110 |
7.0 |
Paloma |
4 |
108 |
1.29 |
209 |
15 |
0.2 |
28 |
2.3 |
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Category |
Vein |
Tonnes
(000) |
Ag
(g/t) |
Au
(g/t) |
Ag Eq
(g/t) |
Contained Metal |
Average
Thickness (m)* |
Ag (koz) |
Au (koz) |
Ag Eq (koz) |
|
Fortuna |
23 |
141 |
0.43 |
174 |
106 |
0.3 |
131 |
3.4 |
Stockwork |
103 |
125 |
0.75 |
183 |
413 |
2.5 |
606 |
6.3 |
Stockwork 2 |
63 |
215 |
1.14 |
304 |
435 |
2.3 |
614 |
4.4 |
Stockwork 3 |
10 |
409 |
1.77 |
547 |
133 |
0.6 |
178 |
3.0 |
Stockwork 4 |
27 |
114 |
0.64 |
164 |
101 |
0.6 |
145 |
3.1 |
Diedro Vein 2 |
26 |
103 |
0.96 |
178 |
87 |
0.8 |
150 |
5.3 |
Victoria (Vmz) |
440 |
143 |
1.16 |
233 |
2,019 |
16.5 |
3,304 |
4.0 |
Victoria HW1 |
115 |
135 |
1.08 |
219 |
500 |
4.0 |
813 |
5.3 |
Total |
1,029 |
147 |
1.04 |
229 |
4,873 |
34.5 |
7,563 |
5.0 |
Refer to notes on Mineral Resources below Table 14.10
Mineral Resources in Table 14.11 are not additive to the Mineral Resources
reported in Table 14.9 or Table 14.10
*Average thickness calculated by spearing the block model at 2 m intervals
in an east to west direction |
An important addition to the Indicated and Inferred
Mineral Resources has been attributed to the exploration and infill drilling programs focused on the Victoria main structure, part of
the Victoria mineralized zone, located approximately 350 m east of the Trinidad deposit.
Due to the presence of high-grade regions in the
Trinidad deposit there is the potential to selectively mine higher-grade material if weaker metal prices dictated that this was necessary.
| 14.12.4 | Comparison to previous estimates |
The primary reasons for changes in the reported
Mineral Resources compared to the previous estimate are due to:
| · | Exploration and infill drilling of the Trinidad
deposit and Victoria mineralized vein. |
| · | Production related depletion and sterilization
of material mined out since the previous estimate. |
| · | Updates in geological reinterpretation. |
| · | Exploration and infill drilling of the Victoria
mineralized zone. |
| · | Change in cut-off grades in relation to increases
in operating costs. |
| 14.13 | Sequential Gaussian Simulation |
Simulation has been employed to estimate the variable
nature of the silver and gold grades in the veins of the Trinidad deposit for risk analysis purposes.
Simulation, as stated by Sinclair and Blackwell
(2002), ‘involves an attempt to create an array of values that has the same statistical and spatial characteristics as the true
grades; however, values are generated on a much more local scale than that for which true grade information is available. If the simulated
data, which reproduces the variance of the input data, both in a univariate sense (histogram models) and spatially (variogram models),
honors the known sample points the technique is conditional simulation, as first described by Journel (1974). The simulation is not an
estimate but a set of values that have the same general statistical character as the original data. A simulation approach will reflect
local grade variations, as simulated arrays of values are constructed to vary on the same scale as the true variations of sample grades,
whereas most estimation methods, such as kriging,
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will smooth the spatial distribution of grade and lower the variance compared to the
true block values (Ravenscroft, 1992).
The simulation produces values (i.e. grades) at
the nodes of an extremely fine grid such that the character of the simulated deposit or domain is almost perfectly known by a large set
of punctual values. The geostatistical simulation generates an equal probable image of reality. Simulation is then repeated, (e.g. 50
times) resulting in a different set of values (realizations) for the grid nodes each time. The sequence of nodes to be simulated is random,
incorporating the samples within a specified search ellipse and the input model, to generate the new grid. The random sequence of points
ensures that each realization is unique while adhering to the same input models. Accuracy of the realizations is dependent on the methodology
used and quality of data provided. Kriging will only provide an average estimation whereas the realizations of the simulation when combined
will approximate the kriged estimate.
Sequential Gaussian simulation was chosen for
simulating the silver and gold grades for veins in the Trinidad deposit. By simulating grades into a fine grid of nodes and re-blocking
to the SMU, conditional bias is eliminated, and recoverable resources can be reported at the SMU scale. This methodology is designed to
reduce the effect of localized over-smoothing of grades and provide a superior comparison between the resource model and what is recovered
underground during grade control.
Sequential Gaussian simulation was run using the
SGSIM process of GSLIB. Sequential Gaussian simulation is performed using the following steps: -
| 1) | The node grid, normal score sample data and variography are input into the
SGSIM process. Search neighborhoods were set to match the orientation and distances as modeled in the variograms (Table 14.5). |
| 2) | A random path is set up so each node is visited once. |
| 3) | The first node is kriged using simple kriging based on the sample data within the specified search ellipse. |
| 4) | A cumulative distribution frequency (CDF) is generated for the node using the estimated mean and kriging
variance. Sequential Gaussian simulation kriges using Gaussian data, which has a symmetrical distribution, subsequently the estimated
mean approximates the mean of the normal distribution, and the kriging variance approximates the variance of the normal distribution. |
| 5) | A value is randomly sampled from the CDF using a Monte Carlo simulation and assigned to the node. |
| 6) | The process then moves to the next node and is repeated, using the original sample data and the previously
simulated nodes. |
| 7) | This is repeated until all nodes have been simulated. |
| 8) | Once all nodes are simulated the process begins again with a new random path to produce successive realizations.
All are different and all are equi-probable. |
The variability that is incorporated in the simulations
depends on the spread of the CDF (step 4). In sequential Gaussian simulation this is a factor of the kriging variance and hence is a factor
of the variogram and the data spacing. Sequential Gaussian simulation assumes strict stationarity in the data as it uses simple kriging.
This means that the mean and variance should be consistent across a domain.
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Upon completion of the sequential Gaussian simulation
process the simulated node values are back-transformed from a Gaussian distribution to the original grade distribution using the BACKTR
program from GSLIB.
The simulations are re-blocked to the SMU size
of interest (2 x 2 x 2 m) therefore creating 50 potential realizations of the deposit.
The simulated models are used for risk analysis
to assess the potential effect of grade variability on the mine plan.
| 14.14 | Comment on Section 14 |
The QP is of the opinion that the Mineral Resources
for the San Jose Mine, which have been estimated using core drill and channel data, have been performed to industry best practices, and
conform to the requirements of CIM (2014). The Mineral Resources are acceptable to support declaration of Mineral Reserves.
It is the opinion of the QP that through the application
of a silver-equivalent value taking into consideration the average metallurgical recovery and long term metal prices for each metal, and
the determination of a reasonable cut-off grade using agreed upon commercial terms, average grade in concentrate, actual operating costs,
as well as the exclusion of Mineral Resources identified as being isolated or economically unviable using a floating stope optimizer,
the Mineral Resources have reasonable prospects for eventual economic extraction.
There are no other environmental, legal, title,
taxation, socioeconomic, marketing, political or other relevant factors known to the QP that would materially affect the estimation of
Mineral Resources that are not discussed in this Report.
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15 | Mineral Reserve Estimates |
| 15.1 | Mineral Resources handover |
The Mineral Resources reported in Table 14.10
contain mineralization that has been classified into the Measured, Indicated and Inferred Mineral Resource categories.
Upon receipt of the block model, a review was
conducted to confirm that the Mineral Resources were reported correctly and to validate the various fields in the model.
For estimating Mineral Reserves, only Measured
and Indicated Mineral Resources that are considered accessible in Trinidad and Victoria have been considered. Inferred Mineral Resources
were treated as waste material.
The Mineral Reserve estimation process considered
the Mineral Resources above a 115 g/t Ag Eq cut-off grade.
| 15.2 | Mineral Reserve methodology |
The Mineral Reserve estimation procedure for the
Trinidad deposit and Victoria mineralized zone are defined as follows:
| · | Review of Mineral Resources in longitudinal sections
and grade–tonnage curves. |
| · | Identification and removal of inaccessible Mineral
Resources based on current mining practices - such as crown pillars and isolated areas. |
| · | Dilution of tonnes and grades based on factors
estimated by the Cuzcatlan mine planning department based on dilution levels encountered during the previous 12 months of production preceding
Mineral Reserve estimation. |
| · | After obtaining the resources with diluted tonnages
and grades, the value per tonne of each SMU is determined based on metal prices and metallurgical recoveries for each metal. |
| · | A breakeven cut-off grade is determined based
on operational costs of production, processing, general expenses and administrative, and distribution costs (total operating cost in US$/t)
and converted into a silver equivalent grade. If the silver equivalent grade of an SMU is higher than the breakeven cut-off grade, the
SMU is considered as part of the Mineral Reserve; otherwise, the SMU is regarded as part of the Mineral Resource. This evaluation is conducted
in Datamine’s Mineable Stope Optimizer software (MSO). |
| · | Evaluate location and dimensions of potential
pillars based on the proposed mining methodology. |
| · | Removal of inaccessible areas and material identified
as pillars or crown pillars to account for mining recovery based on current mining practices and mine architecture. |
| · | Depletion of Mineral Reserves and Mineral Resources
exclusive of reserves relating to operational extraction between July 1 and December 31, 2023. |
| · | Reconciliation of the reserve block model against
mine production between July 1 and December 31, 2023, to confirm estimation parameters. |
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| · | Mineral Reserve tabulation and reporting as of December 31, 2023. |
| 15.3 | Key Mining Parameters |
Mining recovery levels vary due to the geometry
of the vein and geotechnical characteristics of the material being mined. Some mineralized material cannot be economically extracted due
to its isolated location, thickness being below the minimum mineable width, or due to other technical or economic considerations.
In overhand cut and fill (OCF), if the vein width
is greater than 12 m, mining recovery averages 84 %; between 5 and 12 m, it averages 92 %; whereas if the vein width is 5 m or less mining
recovery averages 98 %. In sublevel stoping (SLS), mining recovery averages 92%. In addition, there is a necessity for leaving crown pillars
for each main mine level or sublevel to allow access to the mineralization.
The overall mining recovery is approximately 92
% which takes into account the presence of pillars in wide veins and crown pillars for each main level of the mine.
Dilution refers to the waste material (below breakeven
cut-off grade) that is not separated from the ore (above breakeven cut-off grade) during mining. Dilution increases ore tonnage while
decreasing its grade. It can be defined as the ratio of the tonnage of waste against the total tonnage of ore sent to the mill and is
usually expressed as a percentage (William et al, 2001) equation number 1.
Two sources of dilution have been considered for
estimating Mineral Reserves, operational dilution and mucking dilution.
Operational dilution
Operational dilution was calculated based on mine
production data from June 2022 to July 2023 by the Planning Department of Cuzcatlan and their effect in determining the Stope
dimension that includes planned and unplanned dilution. The process is based on making a comparison of the actual material extracted during
mining (mineral extracted) against the planned ore predicted by the reserve block model (Figure 15.1).
Operational dilution was assessed by comparing
the geologic structure of the vein (as modeled by the Geology Department) and what was planned for extraction (Planning Department). Waste
material is considered to contain no precious metals with silver and gold grades set at a zero gram per tonne value. The data is evaluated
in Datamine using macros.
The results of this evaluation, taken in conjunction
with operational experience, indicate that operational dilution for OCF averages 13.4 % if a zero grade for the waste material is applied.
In case of SLS the operation dilution averages 16.7%
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Figure 15.1
Idealized diagram demonstrating the methodology for determining operating dilution
Figure sourced from William et al (2001)
Mucking dilution
Mucking dilution
is based on the underground surveys of the stopes and calculates the percentage of back fill extracted during mucking in OCF mining method.
Based on this criterion and the 12 months of production preceding the Mineral Reserve estimation this factor has been estimated
at 1.05% applied in both mining methods. Back fill is considered to contain no mineralization with silver and gold grades set at a zero
gram per tonne value.
Based on the estimated operational and mucking
dilution factors related to reserves as of June 2023, the total dilution for the mine in OCF is as follows:
Total dilution = 13.4 % operational dilution + 1.05 % mucking
dilution = 14.5 %.
The total dilution for the mine in SLS is as follows:
Total dilution = 16.7 % operational dilution + 1.05 % mucking
dilution = 17.8 %.
| 15.3.3 | Metal prices, metallurgical recovery, and NSR values |
Metal prices used for Mineral Reserve estimation
were determined as of June 2023 by the corporate financial department of Fortuna from market consensus.
Metallurgical recoveries were based on metallurgical
test work and operational results at the plant from July 2022 to June 2023.
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NSR values were dependent on various parameters
including metal prices, metallurgical recovery, price deductions, refining charges and penalties as detailed in Table 15.1.
Table 15.1
Parameters used for NSR determination
Item |
Unit |
Silver |
Gold |
Metal Price (a) |
US$/oz |
23.90 |
1,880 |
Metallurgical recovery (b) |
% |
90.5 |
89.8 |
Value after Met. Recovery (c) |
US$/oz |
21.64 |
1,688.66 |
Deduction (d) |
% |
95.88 |
95.41 |
Refining Charges (e) |
US$/oz |
-0.68 |
-12.50 |
Loss in process (f) |
US$/oz |
-0.06 |
-4.43 |
Penalty for Zn+Pb (k) |
US$/oz |
-0.06 |
0 |
Premium (g) |
US$/oz |
0.22 |
0 |
Payable metal (h) |
US$/oz |
20.18 |
1,594.14 |
Extraordinary mining fee (i) |
% |
0.5 |
0.5 |
Value – (j) |
US$/oz |
20.08 |
1,586.16 |
Notes:
c = (a x b)/100
h = (c x d-(e + f + g + k))
j = (h x i)/100 |
The results presented correspond to the Progreso
II BIS concession. The Reduccion Taviche Oeste concession is subject to an additional 2.5 % royalty which when applied results in NSR
values of US$ 19.57/oz for silver and US$ 1,546.31/oz for gold.
The Progreso concession is subject to an additional
3 % royalty which when applied results in NSR values of US$ 19.47/oz for silver and US$ 1,538.34/oz for gold.
| 15.4 | Cut-off grade determination |
A breakeven cut-off grade was determined based
on all variable and fixed costs applicable to the operation. These include exploitation and treatment costs, general expenses and administrative
and commercialization costs (including concentrate transportation). Operating costs used to calculate the breakeven cut-off grade for
Mineral Reserve estimation are detailed in Table 15.2.
Table 15.2
Operating cost by area and mining method
Area |
Cost (US$/t) OCF |
Cost (US$/t) SLS |
Mine |
49.83 |
38.31 |
Plant |
20.79 |
20.79 |
General services |
11.87 |
11.87 |
Administrative services |
7.42 |
7.42 |
Distribution |
6.63 |
6.63 |
Total operating cost |
96.54 |
85.02 |
Based on the above operating costs per mining
method, metal prices, metallurgical recoveries, and refining charges, the breakeven cut-off grade was determined for the three separate
concessions where Mineral Reserves are present as follows:
| · | Progreso II BIS concession - 150 g/t Ag Eq for
OCF and 132 g/t Ag Eq for SLS. |
| · | Reduccion Taviche Oeste concession - 153 g/t
Ag Eq cut-off grade for OCF and 135 g/t Ag Eq for SLS. |
| · | Progreso concession - 154 g/t Ag Eq in OCF and
136 g/t Ag Eq for SLS. |
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SLS mining is planned for 82 % of the Mineral
Reserves with OCF comprising the remainder.
The cut-off grade determination does not include
costs associated with management fees, community support activities, institutional relations, capital expenditures, SG&A expenses,
Brownfields exploration or closure costs.
Mineral Reserves reported by vein at the point
of delivery to the process plant are summarized in Table 15.3 based on the cut-off grades detailed above as of December 31, 2023.
Measured Resources have been converted to Proven Reserves and Indicated Resources have been converted to Probable Reserves. The Qualified
Person for the estimate is Raul Espinoza, FAusIMM (CP), a Fortuna employee.
Table 15.3
Mineral Reserves as of December 31, 2023
Category |
Vein |
Tonnes
(000) |
NSR
(US$/t) |
Ag
(g/t) |
Au
(g/t) |
Ag Eq
(g/t) |
Proven |
Bonanza |
18 |
191 |
207 |
1.26 |
305 |
Trinidad |
1 |
135 |
145 |
0.91 |
216 |
Fortuna |
15 |
140 |
126 |
1.24 |
223 |
Stockwork Norte |
0 |
154 |
155 |
1.08 |
239 |
Stockwork 2 |
2 |
194 |
222 |
1.11 |
309 |
Total |
37 |
168 |
172 |
1.23 |
267 |
Probable |
Bonanza |
144 |
145 |
146 |
1.10 |
232 |
Bonanza - Trinidad Norte |
25 |
218 |
248 |
1.25 |
346 |
Bonanza Hanging Wall Splay |
8 |
296 |
313 |
2.04 |
473 |
Trinidad |
235 |
120 |
131 |
0.77 |
191 |
Trinidad Foot Wall 2 |
29 |
114 |
129 |
0.66 |
181 |
Trinidad Foot Wall 3 |
81 |
153 |
181 |
0.80 |
244 |
Paloma |
5 |
121 |
113 |
0.96 |
187 |
Fortuna |
47 |
126 |
122 |
1.00 |
201 |
Stockwork |
81 |
162 |
163 |
1.23 |
259 |
Stockwork Norte |
27 |
186 |
204 |
1.17 |
295 |
Stockwork 2 |
8 |
310 |
344 |
1.91 |
493 |
Stockwork 3 |
6 |
174 |
208 |
0.87 |
276 |
Total |
695 |
145 |
155 |
0.97 |
231 |
Total Proven + Probable Reserves |
733 |
146 |
156 |
0.98 |
233 |
Notes:
| 1. | Mineral Reserves are reported at the point of delivery to the process plant using the 2014 CIM Definition
Standards. |
| 2. | Mineral Reserves are reported as of December 31, 2023. |
| 3. | Raul Espinoza, FAusIMM (CP), a Fortuna employee, is the Qualified Person for estimate. |
| 4. | Mineral Reserves are reported based on underground mining within optimized stope designs using an NSR
breakeven cut-off for cut and fill mining methods of US$ 96.54/t, equivalent to 150 g/t Ag Eq and an NSR breakeven cut-off for sublevel
stoping mining methods of US$ 85.02/t, equivalent to 132 g/t Ag Eq. An additional 2.5 % royalty is applied to the cut-off for Mineral
Reserves mined from the Reduccion Taviche Oeste concession and a 3.0 % royalty is applied to the cut-off for Mineral Reserves mined from
the Progreso concession. |
| 5. | Metal prices used in the NSR evaluation are US$ 23.9/oz for silver and US$ 1,880/oz for gold. |
| 6. | Metallurgical recovery values used in the NSR evaluation are 90.5 % for silver and 89.8 % for gold based
on actual plant recoveries. |
| 7. | NSR values taking into account refining charges used in the estimation are US$ 20.08/oz for silver and
US$ 1,586.16/oz for gold with the exception of material located in the Reduccion Taviche Oeste |
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| | concession where NSR values are US$ 19.57/oz
for silver and US$ 1,546.31/oz for gold and Progreso concession where NSR values are US$ 19.47/oz for silver and US$ 1,538.34/oz for gold. |
| | |
| 8. | Costs used in NSR breakeven cut-off determination are US$ 49.83/t for cut and fill mining method; US$
38.31/t for sublevel stoping mining method; US$ 20.79/t for processing; and US$ 25.92/t for other costs including distribution, general
service and administration. |
| 9. | Mining recovery is estimated to average 92 % and mining dilution is estimated at 17 %. |
| 10. | Mineral Reserve tonnes are rounded to the nearest thousand. |
| 11. | Totals may not add due to rounding. |
Factors that may affect the estimates include:
metal price and exchange rate assumptions; changes to the assumptions used to generate the cut-off grade; changes in local interpretations
of mineralization geometry and continuity of mineralized zones; changes to geological and mineralization shape and geological and grade
continuity assumptions; variations in density and domain assignments; geometallurgical assumptions; changes to geotechnical, mining, dilution,
and metallurgical recovery assumptions; change to the input and design parameter assumptions that pertain to the conceptual stope designs
constraining the estimates; and assumptions as to the continued ability to access the site, retain mineral and surface rights titles,
maintain environment and other regulatory permits, and maintain the social license to operate.
There are no other known environmental, legal,
title, taxation, socioeconomic, marketing, political or other relevant factors that would materially affect the estimation of Mineral
Reserves that are not discussed in this Report.
| 15.6 | Comment on Section 15 |
Mineral Reserves
are to be extracted using OCF and SLS underground mining methods. In the opinion of the QP, Mineral Reserves appropriately estimated with
the application of reasonable mining recovery and dilution factors based on operational observations and a silver equivalent breakeven
cut-off that is based on actual mining, processing and smelting costs; actual metallurgical recoveries achieved in the plant; and
reasonable long-term metal prices that are based on market consensus.
The QP is of the opinion that the Proven and Probable
Mineral Reserves estimate has been undertaken with reasonable care and has been classified using the 2014 CIM Definition Standards.
There are no other environmental, legal, title,
taxation, socioeconomic, marketing, political or other relevant factors known to the QP that would materially affect the estimation of
Mineral Reserves that are not discussed in this Report.
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Mining method selection is critical as it impacts
dilution, productivity, product consistency, production capacity, development, backfill and ventilation requirements. The mining method
applied at the San Jose Mine is OCF and SLS using a mechanized extraction methodology. Production capacity has been 3,000 tpd since 2016.
All mine planning, hydrogeology, geotechnical
assessment, mine services, ventilation, and electric power supply evaluations are undertaken by the Mine Planning & Engineering
department of Cuzcatlan.
A study conducted by Cardona Benavides &
Asociados S.C. in 2022, indicates that the groundwater balance shows inflow rates ranging from 12.57 l/s to 10.02 l/s and outflow rates
ranging from 10.02 l/s to 3.28 l/s. The inflow rates account for the required storage works for drainage, such as ponds or pumping pools
used for water extraction to the surface. The outflow rates identify the volumes of groundwater reintegrated daily into the mine system.
Based on the hydrogeological knowledge derived
from the study, it was found that the water table associated with wells, and springs supplying the different communities in the area of
interest does not have a direct connection with the saturated zone identified at depth within the mine. As a preliminary approximation,
the elevation of the saturation zone is considered to be at 980 meters above sea level, with the deepest mine level located at 830 meters
above sea level.
Considering the volumetric water flow extracted
from the mine to the surface, which averages 10 l/s monthly, and taking into account the estimated inflow of water into tunnels beneath
the water column, along with the projected monthly progress within the mine, there could be a potential increase in groundwater flow to
the mine, estimated at around 6 l/s or roughly 16,400 m3/month, with a possible maximum of approximately 13 l/s, equivalent
to 33,400 m3/month. The pumping equipment capacity ranges from 28 to 30 l/s and operates for less than 24 hours per day, so
it may be necessary to extend its operational hours when the maximum drainage flows from the deepest mine area to the ground surface are
reached. The mine dewatering system is discussed in Section 16.7.8.
Cuzcatlan’s geomechanics department evaluates
the rock mass classification for the active areas in the mine based on the following systems:
| · | Geological strength index (GSI) as described
by Marinos et al (2007). |
| · | Rock mass rating (RMR) that uses the Bieniawski
(1989) classification system. |
RMR and GSI are used as the main systems for ranking
the rock mass at the San Jose Mine from very bad (RMR less than 20), to good (RMR greater than 61) as detailed in Table 16.1.
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Table 16.1
Geomechanical classification used at the San Jose Mine
Classification |
RMR |
Good |
61–80 |
Regular - A |
51–60 |
Regular - B |
41–50 |
Bad - A |
31–40 |
Bad - B |
21–30 |
Very Bad |
0–20 |
The maximum stable opening dimensions have been
estimated based on this rock mass classification and the hydraulic radius for each mineralized structure. For OCF, the maximum stable
size approved for underground mining is 6 to 8 m in width and 6 m in height, while for SLS, openings are 4 m in width and 4 m in height,
with stope dimensions from 15 to 20 m in height.
The average RMR of the rock for the Bonanza and
Trinidad vein systems is 40 to 55, supporting the type of openings indicated for the OCF mining methodology (using paste backfill or waste
rock fill). The ground support designed for the OCF stope openings is 2.4 m (8-foot) long bolts and a 5.1–7.6 cm (2 to 3-inch) thickness
of shotcrete. To ensure appropriate support is achieved in a timely manner, three robot shotcrete machines and four bolters have been
incorporated into the mining fleet. For SLS, the rock support consists of cable bolting of length from 8 to 14m.
When the mineralized structure is greater than
8 m in width, such as in the Stockwork Zone areas, exploitation is performed with a combination of OCF and room-and-pillar methods for
ground support stability. Pillars of either 6 by 4 m (24 m2 area) or 5 by 5 m (25 m2 area) were recommended
by third-party consultants SVS (2015). For SLS, the use of rib pillars from 3 to 6 m in thickness is recommended, with thicknesses based
on the width of the mineral structure.
The methods chosen for underground mining are:
OCF removes ore in horizontal slices, starting
from the bottom undercut and advancing upwards. When ore widths are greater than 8 m, a combination of OCF and room-and-pillar methods
were selected as the most appropriate for the conditions encountered.
Mechanized mining uses a Jumbo drill rig to drill
blast holes, scoop trams for loading and trucks for ore haulage. Rock support is provided through rock bolts and shotcrete. The deposit
width ranges from 4.5 m to 17 m for the Bonanza and Trinidad vein systems and can be more than 30 m in the Stockwork Zone. Mechanized
mining is regarded as the only methodology suitable for all veins based on the geological structure and geotechnical studies to date (Section 16.3).
The mechanized mining sequence is demonstrated in Figure 16.1 and includes: drilling (with a Jumbo drill rig), blasting, support, loading
(by scoop tram) and haulage:
| 1. | Economic minerals are extracted from the stope in horizontal slices that open the entire width and length
of the stope using pivot ramps that goes from up to ±15 % gradient. |
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| 2. | After the stope has been mined out, voids are backfilled with paste or waste rock. The key performance
indicators for this activity are set at 85 t/h production rates for rock waste and 100 to 150 t/h for paste fill. |
| 3. | Drilling of horizontal slices is conducted in sections of 6 m by 6 m by mechanized jumbos which have a
boom length of 5 m. |
| 4. | The blast pattern is charged with an explosive made up of emulsion and ammonium nitrate fuel oil (ANFO).
The average power factor applied in the blasting is 0.45 kg/t for stopes. After the mine face has been blasted and ventilated, scaling
of loose rock is conducted. This is an important phase of the mining cycle in terms of safety due to the risk of falling rock. |
| 5. | Mucking is done by scoop trams (6 yd3 capacity) from the face to an underground stockpile in
the stope. Trucks with 14 m3 capacity transport the broken ore from the stopes to the surface stockpiles using a paved ramp
which allows speeds of up to 25 km/h. |
| 6. | Required support is defined by the geomechanics department. |
Figure 16.1
Mechanized mining sequence
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Figure prepared by Cuzcatlan 2023.
Mineralization is removed by preparing two levels
that create blocks to extract. The extraction is from the bottom level. The blocks of SLS have rib pillars depending on the rock type
and general ground conditions.
Mechanized mining uses a Jumbo drill rig to support
the rock, Stopemaster, Stinger and Raptor rigs to drill blast holes, scooptrams for loading and trucks for haulage. Rock support is provided
through rock bolts and shotcrete. These areas have width ranges from 2 m to 6 m. The mechanized mining sequence includes: ground support,
drilling (with long hole drilling equipment), blasting, loading (by scooptram), haulage and filling:
| 1. | In the sublevel the required support is defined by the geomechanics department. |
| 2. | Drilling of vertical slices is conducted in width depending on the width of the vein by equipment such
as a Stopemaster or Stinger and Raptor which have a length of 10 to 20 m. |
| 3. | The blast pattern is charged with an explosive made up of emulsion and ANFO. The average power factor
applied in blasting is 0.39 kg/t. |
| 4. | After the sections have been blasted and ventilated, mucking is done by scoop trams (6 yd3 capacity)
from the mining face to an underground stockpile near the stope. Trucks with 14 m3 capacity transport the broken material from
the stopes to the surface stockpiles using a paved ramp which allows speeds of up to 25 km/h. |
| 5. | After the stope has been mined out, voids are backfilled with paste fill or waste rock fill. The key performance
indicators for this activity set 85 t/h production rates for rock waste and 100 to 150 t/h for paste fill. |
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| 16.5 | Mine production schedule |
Mineral Reserves will sustain a 12-month LOMP
consisting of 350 production days a year. Table 16.2 presents the LOMP for a mill throughput of 2,100 tpd. Based on the evaluation
using MSO, the LOMP production will be approximately 3.2 Moz of silver and 20 koz of gold based on an average head grade of 156 g/t Ag
and 0.98 g/t Au. Inferred Mineral Resources totaling 1.0 Mt averaging 147 g/t Ag and 1.04 g/t Au are not taken into consideration in the
LOMP evaluation.
Table 16.2
San Jose Mine life-of-mine production plan 2024
Item |
Q1 |
Q2 |
Q3 |
Q4 |
Total* |
Ore milled (kt) |
161 |
169 |
200 |
203 |
733 |
Ore grade Ag (g/t) |
185 |
139 |
150 |
139 |
156 |
Ore grade Au (g/t) |
1.10 |
0.83 |
0.98 |
0.93 |
0.98 |
Metal recovery Ag (%) |
91 |
90 |
90 |
90 |
91 |
Metal recovery Au (%) |
90 |
89 |
89 |
89 |
89 |
Concentrate production (t) |
5,172 |
5,287 |
6,283 |
6,340 |
23,082 |
Concentrate grade Ag (g/t) |
5,236 |
4,024 |
4,306 |
4,015 |
4,370 |
Concentrate grade Au (g/t) |
31 |
24 |
28 |
26 |
27 |
Ag metal production (koz) |
871 |
684 |
870 |
818 |
3,243 |
Au metal production (koz) |
5 |
4 |
6 |
5 |
20 |
Note: Totals
may not add due to rounding
The SMU has been determined to be 2 m by 2 m by
2 m, however, the mining unit is determined by the mining block or envelopes generated in Datamine’s MSO software based on the width
of the mineralized vein and the minimum mining width that depend on the mining method to be applied. This is 4 m width by 5.5 m height
for OCF methods, and 2 m width by 20 m height for SLS. One blast rounds of 3.5 m are used in both mining methods.
Dilution factors are estimated to be approximately
17% for all veins based on the proposed mining methodology. Waste material is considered to contain no mineralization with silver and
gold grades set at a zero gram per tonne value.
| 16.5.1 | Mineable stope optimization |
Datamine’s MSO was used to develop the indicative
mineable envelopes at the given cut-off grades. MSO utilizes key inputs to generate an optimized stope shape whereby the mined metal in
relation to tonnage is optimized. The optimization is driven by the following inputs:
| · | Minimum and maximum stope widths. |
| · | Minimum and maximum dip angles. |
The stope design is optimized by performing the
following steps:
| 1. | Generation of mineable areas. This process requires the following inputs: |
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| a. | Height of the operational slice; 5.5 m high has been considered for the optimization in OCF; then 10–20
m high has been considered for SLS. |
| b. | Width of the operational slice; a minimal operational width of 4 m was applied. |
| c. | A breakeven NSR cut-off equivalent to US$ 96.54 /t for OCF and US$ 85.02 /t for SLS (see Table 15.2). |
| d. | Dip and strike of the vein. |
| e. | The resource block model. |
| 2. | MSO outputs were imported into Datamine’s UG planner to evaluate and remove extraneous satellite
stopes that are not conducive to practical and/or economic extraction. Mineralized material identified inside the MSO three-dimensional
wireframes represents the Mineral Reserves. Figure 16.2 shows the longitudinal section of the optimized stopes. The result is used as
an input for production and related development infrastructure planning and sequencing. |
Figure 16.2
Optimized mineable areas for the San Jose Mine
Figure prepared by Cuzcatlan, 2023
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| 16.6 | Underground mine model |
Access to the San Jose Mine is from surface through
a main ramp with a total average gradient of 10 % and dimensions of 4.5 m width by 4.5 m height. A longitudinal section of the mine layout
is displayed in Figure 16.3.
Figure 16.3
Mine layout
Figure prepared by Cuzcatlan, 2023
The San Jose Mine has been designed with a separation
of 100 m between levels primarily to limit blast vibration but also to assist with hanging wall and footwall stability.
The ventilation requirements for the mine to produce
2,100 t/d is 615,593 cfm. The ventilation system brings all the intake air through the main ramp and three main airway networks. Exhaust
air is forced to the surface from inside the mine by three principal fans, two operating at 250,000 cfm and one at 120,000 cfm.
| 16.6.2 | Lateral development |
The San Jose Mine requires approximately 7,691
m of lateral development of which 90 % is for preparation and lateral advance requirements, 10 % for development (Table 16.3).
Table 16.3
Lateral development for the San Jose in 2024
Activity |
Q1 |
Q2 |
Q3 |
Q4 |
Total |
Preparation (m) |
1,870 |
1,938 |
2,024 |
1,098 |
6,929 |
Development (m) |
198 |
279 |
249 |
35 |
762 |
Total (m) |
2,068 |
2,217 |
2,272 |
1,133 |
7,691 |
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| 16.6.3 | Raising requirements |
A total of
273 m of vertical development is required for the LOMP as detailed in Table 16.4.
Table 16.4
Vertical development for the San Jose in 2024
Activity |
Q1 |
Q2 |
Q3 |
Q4 |
Total |
Development (m) |
178 |
0 |
0 |
95 |
273 |
Total (m) |
178 |
0 |
0 |
95 |
273 |
| 16.7 | Equipment, manpower, services, and infrastructure |
| 16.7.1 | Contractor development |
The San Jose Mine is operated by a combination
of Cuzcatlan employees and mining contractors selected by Cuzcatlan based on a competitive bidding process.
The mining contractor will generally include activities
such as drift development, stope preparation, exploitation, rock bolting support, and backfilling of waste rock fill.
The current mining fleet is sufficient for the
LOMP and consists of the following equipment:
| · | Seven Scooptrams of 6 yd3 capacity. |
| · | Four electric hydraulic Jumbo drill rigs with
two arms. |
| · | One electric hydraulic Jumbo drill rig. |
| · | Seven electric hydraulic bolter Jumbo drill rigs. |
| · | Twelve trucks of 14 m3 capacity. |
| · | Seven trucks of 7 m3 capacity. |
| · | Five concrete mixer trucks. |
| · | Five telehandlers (telescopic). |
| · | Two utility trucks (diesel-oil). |
| · | Four long hole drilling machines. |
San Jose Mine management estimates that a total
of 1,162 employees, consisting of 465 contractors and 697 Cuzcatlan staff, are required for operation related activities in 2023 with
similar numbers maintained over the LOMP.
| 16.7.4 | Underground drilling |
The underground mine uses several different drilling
techniques and equipment including:
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| · | Mechanized drilling for horizontal and decline
drifts using electro-hydraulic Jumbo drill rigs. |
| · | Mechanized long hole drilling equipment such
as Stopemaster or Stinger and Raptor. |
| 16.7.5 | Ore and waste handling |
Transportation of
ore and waste is done via trucks with a 14 m3 and 7m3 of capacity through the main and secondary ramps. The
main ramp has been designed with two different gradients, the first is associated with straight sections being 12 %, and the second is
associated with curved sections being 6 % with a curvature radius of 17 m. To optimize the transportation velocity, the mine has paved
the ramp wheel pathways with a compression resistance of 210 kg/cm2. This construction allows the trucks to increase speeds
from 8 km/h to a maximum of 25 km/h.
Air requirements
at the mine have been analyzed in accordance with the Mexican Regulation NOM-023-STPS-2012.
Ventilation at the mine considers:
| · | The main ventilation system. |
| · | Auxiliary ventilation system (for stopes and
blind developments). |
For optimal performance
of the operation, and to provide adequate ventilation to the working faces, the required air flow is 615,593 cfm taking into account
the total number of people working inside the mine and the total amount of equipment required to accomplish daily tasks (Table 16.5).
Table 16.5
Mine air flow requirements
Item |
Diesel Equipment |
Equipment
Power (hp) |
Simultaneous Use
(%) |
Quantity |
Requirement
(75 cfm / hp) |
1 |
DDH rig |
80 |
60 |
3 |
8,665 |
2 |
Supervisor light vehicles |
174-383 |
24 |
24 |
45,557 |
3 |
Truck |
230-361 |
44 |
25 |
264,047 |
4 |
Scooptram (6 yd3) |
250-343 |
66 |
10 |
117,067 |
5 |
Jumbo |
78-147 |
26 |
5 |
11,481 |
6 |
Bolter |
75-160 |
47 |
8 |
21,484 |
7 |
Scissor |
75-110 |
58 |
8 |
23,245 |
8 |
Mixer |
160 |
62 |
5 |
22,524 |
9 |
Scaler |
94-160 |
40 |
5 |
8,506 |
10 |
Small Mixer |
160 |
57 |
2 |
10,560 |
11 |
Shotcrete Robot |
146 |
40 |
5 |
15,725 |
12 |
Backhoe loader |
94 |
40 |
2 |
4,381 |
13 |
Underground personnel |
|
|
257 |
13,614 |
14 |
Requirement for high temperatures |
|
|
|
19,423 |
15 |
Loss detected by old work (5%) |
|
|
|
29,314 |
Total |
615,593 |
Planned airways into and out of the mine are listed
in Table 16.6. Air intake is through the main access ramp. Exhaust is through two 3 m diameter raise bores.
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The ventilation
network as of September 2023 comprises 95 % of the total design. Ongoing work to support the 3,000 tpd ventilation design is presently
related to the construction of two 3 m diameter raises.
Table
16.6 Air flow in-out balance
Airways |
LOMP (cfm) |
Fresh air |
429,566 (*) |
Exhaust air |
445,117 |
Requirements (**) |
615,593 |
Coverage (%) |
70% |
*
Projected by Ventsim Simulator
**
Mexican regulation (75 cfm/hp)
The mine
uses two kinds of backfill; waste rock backfill generated during underground mining and paste fill. The paste fill is comprised of a
mixture of fine particles from the tailings, cement, and water. It has a solid content of between 70 % and 80 % that ensures consistency
and allows the material to be pumped through a pipe network. Cement is added to help dry the mixture and ensure the fill sets to a specified
minimum level of strength within a reasonable timeframe. Tailings enter the mixture as a main component of the blend with the process
described as follows:
| · | Thickened
tailings come from the concentrator plant and are stored in a continuously agitated tank.
The pulp has an average density of 1500 g/l, equivalent to a solids content of 55 %. |
| · | Filtered
tailings come from the filter plant and have a solids content of 86 %. |
| · | Portland
cement is supplied via a 190 t silo and represents 3 % of the dry solids of the tailings. |
| · | Water
is supplied from the pulp. |
Paste design
resistance is 4 kg/cm2 or 400 kPa with this being achieved after seven days. It is advisable to wait a minimum of seven days
before mucking to ensure the paste fill can handle the weight of the scoop trams.
| 16.7.8 | Mine dewatering system |
The drainage
system of the mine removes any excess water that is encountered underground or produced during drilling activities. To pump water from
underground to surface, five pumping stations have been installed at different levels of the mine, as part of the main drainage system.
Once the water is pumped to surface, a sedimentation process is performed in a 1,000 m3 pond with the cleaner water stored
in a 9,000 m3 pond where it is recycled for reuse in the mine.
The five
pumping stations have settling ponds to allow suspended solids to settle from the water. This water is then poured into a tank of decanted
water where a 150 hp pump moves the clean water with low solids to the upper pumping stations.
The pumping
system in the mine is comprised of four stages, from the bottom of the mine to the surface. The stages include:
| · | Pumping
station 5, located at level 950, pumps water to the 1100 level. |
| · | Pumping
station 4, located at level 1100, pumps water to the 1200 level. |
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| · | Pumping
station 3, located at level 1200, pumps water to the 1300 level. |
| · | Pumping
station 2, located at level 1300, pumps water to the 1400 level. |
| · | Pumping
station 1, located at level 1400, pumps the water to the surface. |
One future
pumping station is planned for construction in 2024, in accordance with the LOMP requirements and will include the following:
| · | Pumping
station 6, to be located at level 800, to pump water to the 950 level. |
Each pumping
station will have two 150 hp pumps (one as a standby), a settling pond, and a pumping chamber.
There are
8 pneumatic pumps, carrying water from the development faces to the aforementioned settling ponds. These pumps can force a flow rate
of 232 gallons per minute allowing a maximum of 10 mm particle size of solids on a static height of 25 m.
The industrial
water required by the mine operation is recovered from the water pumped to the surface via the underground dewatering system. The water
returns to the mine through a 4-inch pipeline network to supply the various drilling requirements.
| 16.7.9 | Maintenance facilities |
A workshop
has been constructed on the 1100 level where the contractor performs maintenance of the load-haul-dump (LHD) equipment. The workshop
is for major, minor and preventive maintenance. The workshop area is approximately 1,500 m2 in area and includes the following:
| · | Washing
area for mechanical equipment. |
| · | Maintenance
area for jumbos and scoops. |
| · | Oil
and lubricants store. |
| · | Welding
area including a ventilation raise. |
To increase
productivity in the Victoria zone, a workshop will be built in 2024 on the 1200 level where the contractor will perform maintenance of
the LHD equipment.
| 16.7.10 | Power distribution |
The mining
unit is connected to the national electric network managed by the Federal Electricity Commission (CFE) through a main feed of 115,000
volts and a secondary line available to supply power to critical equipment in case of power failure or electrical maintenance of the
main line.
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The main
power line supplies two secondary transformers with transform ratios as detailed in Table 16.7. Both transformers work independently,
and for safety purposes, are separated by a concrete wall. Independence of the transformers provides the operation with flexibility to
deal with power failures and to carry out preventative maintenance.
Table
16.7 Transformer capacities
Equipment |
Transformation
relation |
Capacity |
Power
transformer 1 |
115
kV / 13800 volts |
6.7
– 8.4 MVA |
Power
transformer 2 |
115
kV / 13800 volts |
7.5
– 9.37 MVA |
The mining
unit has two main distribution circuits that can support a 3,000 tpd operation.
| · | Circuit
1 - Transformer 1 (13,800 kV, 6.7-8.4 MVA) supplies the following areas: |
| o | Underground
mine – Central main circuit. |
| o | Underground
mine – North main circuit. |
| o | Mine’s
surface facilities. |
| · | Circuit
2 - Transformer 2 (13,800 kV, 7.5-9.37 MVA) supplies the following areas: |
| o | Flotation
(new circuit). |
| o | Underground
mine – North main circuit 13,800 kV. |
| o | Underground
mine compressors area. |
| o | Mechanical/electrical
workshop. |
The power
supply for the underground mine consists of four main circuits with the following provisions:
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| · | Circuit
1 - Transformer 1.1, located at surface with a transformer ratio of 13,800 to 4,160 volts
and a capacity of 2 MVA. This main transformer feeds the northern portion of the mine with
the following distribution: |
| o | Substations
#9, #23 and #24 at 1225 level with a transformer ratio of 4,160 volts to 480 volts all of
them are 1000 kVA which feeds the construction activities for the exploration drifts at this
level (BP084N, Stope Q and CX5G1). |
| o | Substation
#19 at 1100 level with a transformer ratio of 4,160 volts to 480 volts of 1000 kVA which
feeds all the operations power needs for the 1100 level (Stope R, Workshop 30). |
| o | Substation
#5 at 1100 level, with a transformer ratio of 4,160 volts to 480 volts of 500 kVA which supplies
power to a pumping station and drilling activities. |
| · | Circuit
2, comprises a high voltage cable of 13,800 volts connected to a cell with protection relay
and fed from surface to the 900 level in the northern sector of the mine with the following
distribution: |
| o | Substation
at 1350 level with a transformer ratio of 13,800 volts to 480 volts of 1,000 kVA which feeds
all the operational power needs for the main 250,000 cfm fan and Stope P. |
| o | Substation
# 18 at level 1000, with a transformer ratio of 13,800 volts at 480 volts of 1,000 kVA which
feeds all the operational power requirements for the 1000 level station pump #5. |
| o | Substations
#21 and #22 at level 900 and 850 respectively both with a transformer ratio of 13,800 volts
at 480 volts of 1,000 kVA which feeds all the operational power requirements for the deepest
place of the mine. |
| · | Circuit
3, located at surface with a transformer ratio of 13,800 to 4,160 volts with a capacity of
1.5 MVA. This main transformer feeds the central side of the mine with the following distribution: |
| o | Substation
# 4 at 1300 level, with a transformer ratio of 4,160 volts to 480 volts of 750 kVA which
feeds the main 120,000 cfm fan and pumping system 2. |
| o | Substation
#6 and #16 at 1200 level, with a transformer ratio of 4,160 volts to 480 volts of 750 kVA
and 1000 KVA respectively which feeds the operational demands of the 1200 level and the second
250,000 CFM fan. |
| o | Substation
# 10 at 1100 level, with a transformer ratio of 4,160 volts to 480 volts of 1,000 kVA which
feeds the operational demands of the 1100 level as well as the ventilation for the exploration
drift. (Stope W, Stope V and BP777). |
| · | Circuit
4, transformer 1.3 13,800 v / 440 v 750 kVA (2 pieces), these transformers feed the compressors
at surface, contractor offices and the training area of the mine safety brigade. |
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| 16.7.11 | Other services and infrastructure |
Additional
complementary services and infrastructure have been constructed inside the mine and include a compressed air supply; an underground explosive
storage facility; and refuge stations and mine rescue facilities.
Compressed
air supply
Currently
Cuzcatlan has two Atlas Copco GA 250 compressors located at surface with a maximum operating pressure of 8.85 bar and air flow of 1,200
cfm.
The compressed
air network is comprised of a tank after the main compressors with a 7,400-liter capacity. Compressed air is pumped along a 15 cm (6-inch)
main pipeline of 1,450 m length from the surface to the 900 level, with connections between the 1200, 1100, and 1000 levels. A secondary
pipeline network takes the compressed air from the main pipeline to the working areas through a series of pipes. To support the network
two compressed air tanks have been installed at the 1200 and 1100 levels.
Underground
explosive storage
The explosive
storage is comprised of two separate areas that meet the safety and security requirements established by Mexican Federal Regulations.
The facilities are designed to store explosives and blasting accessories separately.
Refuge
station and mine rescue facilities
Safety
is of paramount importance to Cuzcatlan. A network of vertical manway exits has been built to ensure that if a major incident occurs
the workforce has the ability to escape. Additionally, a refuge station has been constructed adjacent to the ramp to provide shelter.
| 16.8 | Comment
on Section 16 |
The QP
is of the opinion that:
| · | The
mining method being used and planned is appropriate for the Trinidad deposit. The underground
mine design, dry stack tailings facility design, and equipment fleet selection are appropriate
to reach production targets and sufficient for the LOMP. |
| · | The
mine life is estimated at just under 12 months. |
| · | The
mine plan is based on successful mining philosophy and planning, and presents low risk. |
| · | Inferred
Mineral Resources are not included in the mine plan. |
| · | Mining
equipment requirements are based on actual operational conditions experienced at the San
Jose Mine producing 2,100 tpd. |
| · | All
mine infrastructure and supporting facilities meet the needs of the current mine plan and
production rate. |
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The following
section provides a description of the current process plant design, including the equipment characteristics and specifications at each
step of the process.
The plant
was designed based on the metallurgical testwork in Section 13 and has been operating for 12 years.
| 17.1 | Crushing
and milling circuits |
The concentrate
plant has a maximum throughput capacity of 3,000 dry tpd. The principal stages are as follows:
| · | Thickening,
filtering and shipping. |
Crushing
at the San Jose Mine is a dry process, where ore extracted from the mine is reduced in size from 406 mm to 12.7 mm to be fed to the mill.
The crushing
process begins at the reception hopper, where ore from the mine is deposited. The ore is fed from the bottom of the hopper via a plate
feeder into a jaw crusher that crushes the ore to a 102 mm product size prior to it being transported via conveyors to one 2.44 m by
6.1 m primary screen deck. The screen deck operates with one mesh of 35 mm opening. Material that does not pass through the 35 mm mesh
is sent to a secondary crusher via a chute, where it is reduced to 25 mm and the product returned to the primary screen deck. The material
that passes the 35 mm mesh is sent via a conveyor to one 3 m by 7.3 m secondary screen deck. The screen deck operates with one mesh of
12.7 mm opening. Material that does not pass through the 12.7 mm mesh is sent to a tertiary crusher where it is reduced to 12 mm size
before being sent back to the jig to close the circuit. The fine ore that passes through 12.7 mm mesh is sent to fine ore storage, achieving
a final product of 12.7 mm that is stockpiled before being fed into the milling circuit.
| 17.1.2 | Milling and classification |
The fine
ore stock is sent via conveyor belts to either a 3.96 m by 5.94 m or 4.57 m by 6.6 m ball mill with 25 to 30 % of their volume filled
with three-inch wrought steel balls used to further reduce (grind) the ore size. The product of the mills is pumped to the classification
process comprised of hydro-cyclones, where two products are generated; 1) a fine ore, which is expulsed thorough the top of the cyclones,
and 2) a coarse ore that exits through the bottom and is recycled back into the mills for further grinding. The fine ore must comply
with the metallurgical conditions for metal recovery, which indicates 80 % of the product must be under the 150-mesh size (equivalent
to 105 µm), before being sent to the flotation process.
The pulp
(water + mineral) received from the fine ore of the hydro-cyclone, is first sent to a flotation stage performed in ten mechanic cells,
six 14.2 m3 and four 17 m3 in size, which generate agitation through a propeller and diffuser that distributes
the pulp and injects air. The agitated pulp allows reagents to act on the elements of value and adhere to the bubbles
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formed
by the injected air, freely spilling over the edges of the cells into a collection trough. The resulting product is known as the primary
concentrate. Upon conclusion of this first stage, the pulp is sent by gravity to a second stage.
The second
flotation stage is similar to the first, utilizing an additional four 17m3 mechanic cells to generate the same conditions,
from this process a secondary scavenger concentrate is obtained. This secondary scavenger concentrate is returned to the beginning of
the 17m3 cells settle. Mineral that did not float in the second flotation stage is regarded as tailings and passes to the
thickening process.
The primary
concentrate from the first two 14.2 m3 cells is sent directly to the third cleaning stage, the rest of the primary concentrate
is sent to a first cleaning stage that is carried out in twelve 2.8 m3 mechanical cells, whose function is to eliminate impurities
and increase the grade of the concentrate. The product obtained is a first clean concentrate and the residue is returned to the first
of the 17 m3 cells to settle. The first clean concentrate is sent to a second cleaning stage performed in three 2.8 m3
mechanic cells having a similar function to the first where impurities continue to be removed to obtain a second clean concentrate
and the residue is returned to the first cleaning stage. The second clean concentrate is sent to a third cleaning stage performed in
two 2.8 m3 mechanic cells to obtain a final concentrate that passes to the thickening stage and a residue that returns to
the second cleaning stage.
| 17.1.4 | Thickening, filtering, and shipping |
The third
cleaning concentrate is sent to a thickening tank where, using a flocculating reagent, the particles are agglomerated, and sediment generated.
Solids and liquids are separated so as to recover water to put back into the process (recovered water) while the thickened solid is pumped
to a two press-type pressure filter of twelve tarpaulin covered plates, where part of the water is eliminated and then re-circulated
to the process. The concentrate cake is discharged from the filters to the concentrate storage for transportation.
The underflow
of the final bank of the second flotation (exhaustion) is sent to a thickening tank where a solid-liquid separation is performed through
the application of a flocculating reagent that agglomerates fine particles into sediment. Recovered water is returned to the process
while the rest of the pulp is pumped to a three press-type pressure filter of one hundred and forty-five tarpaulin covered plates, where
most of the water is eliminated and then re-circulated back into the process. The tailings cake is discharged from the filters to the
tailings stock for transportation to the dry stack disposal area.
Part of
the pulp pumped to the pressure filter is deviated to the paste fill plant for backfilling purposes with 30 % of the backfilling requirements
of the mine being supplied by the paste fill plant.
Figure
17.1 displays the principal components of the processing plant.
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Figure
17.1 Crushing and milling circuits at the San Jose processing plant
Figure prepared
by Cuzcatlan, 2023
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| 17.2 | Requirements for energy, water, and process
materials |
Energy
requirements at the operation are provided by a State power line of 115 kV which supplies two power transformers of 7 to 8 MVA capacity.
The transformers cover the necessities of the underground mine (see Section 16.6.10), the mill plant, and facilities based on the
present 3,000 tpd production rate (8 MVA).
The plant
requires 2.7 m3 of water to process one tonne of ore, of which 92 % comes from the recirculation process, and the remaining
8 % from the waste-water treatment plant in Ocotlan.
Reagent
consumption in the processing plant is detailed in Table 17.1.
Table
17.1 Reagent consumption of the San Jose processing plant
Reagent |
Consumption (g/t) |
Frother |
Ore
Prep 507 |
1 |
Collectors |
Xantato
Amilico de Potasio |
4 |
Aeropromotor
404 |
10 |
Aerophine
3418 |
31 |
Pennfloat-3
|
2 |
Max
Gold |
5 |
Flocculant |
Floculant
Magnafloc 336 |
33 |
Depressor |
Citric
Acid |
90 |
Aluminum
sulfate |
100 |
A difference
between the plant design and functionality has been in the amount of sodium silicate required for the cleaning stages of the flotation
process. The CAM (2010) prefeasibility study had recommended the usage of 100 g/t of sodium silicate reagent, whereas Cuzcatlan
has identified that the use of this reagent is not necessary to obtain the desired product. The plant has made significant cost savings
by reducing the quantity of reagents used. Two reagents were also added to reduce the fluorine concentration in the final concentrate
(citric acid and aluminum sulfate).
| 17.3 | Comment on Section 17 |
The QP
considers processing requirements to be well understood, and consistent based on the actual observed conditions in the operating plant.
There is no indication that the characteristics of the material being mined will change and therefore the recovery assumptions applied
for future mining are considered as reasonable for the LOMP.
The plant
is of a conventional design, is based on conventional equipment, and uses conventional consumables.
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The mine
has a relatively small surface footprint with the operational property boundary split into two parts, a north area (mine property) covering
the mine offices and surface infrastructure footprint (50.15 ha), and a south area (tailings property) covering the area of the
tailings storage facility (69.69 ha). The major surface facilities of the north area where the mine is located are displayed in Figure
18.1.
Figure
18.1 Plan view of mine and processing plant area
Figure
prepared by Cuzcatlan, 2023
Facilities
at the San Jose Mine are connected via unpaved roads that are maintained by the operation (Figure 18.1). Water is applied to the roads
during the dry season to reduce dust pollution.
| 18.3 | Tailing
disposal facilities |
The tailings
disposal facility is located approximately 1.5 km to the southwest of the mining operation (Figure 18.2). There are two types of tailings
disposal: the tailings dam and the dry stack tailings.
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Figure
18.2 Location map of tailings storage facilities
Figure prepared by Cuzcatlan, 2023
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The tailings
dam was designed in three downstream construction phases or stages (Figure 18.3). Phase 3 (S3) was originally divided into two stages;
stage-3a (S3a) and stage-3b (S3b). The S3a raised the crest elevation of the dam from 1,589.8 masl to 1,595 masl, which resulted
in a cumulative storage capacity of 2,300,000 m3 of tailings. The S3a phase was completed in 2014. The plan for stage 3b was
to reach the elevation of 1,598.3 masl extending the storage capacity to 3,000,000 m3 but this stage is no longer required
as all tailings are now filtered and compacted in-situ into dry stack facility.
Figure
18.3 Schematic drawing showing phase 1, phase 2 and phase 3 tailings dam
The dam
is 43.0 m high at the center, providing a storage capacity of approximately 2,300,000 m3 (S3a). The base of the impoundment
has been adapted with the installation of a 300 g/m2 non-woven geo-textile lining to protect the 1.5 mm thick geo-membrane
that covers the entire basin of the dam. The dam received the overflow of the tailings thickener, which was pumped and discharged into
the dam through nine, 6-inch discharge pipes distributed around the tailings impoundment and were opened and closed depending on the
need to distribute the tailings uniformly. Overflow (coarse tailings) was sent to the underground mine for backfilling stopes.
Currently
the dam is used as a contingency for disposal of tailings if a mechanical failure were to occur in the tailings filter plant. The dam
is also used to store excess water from underground workings as supplemental process water storage during the wet season to be later
used in the dry season.
In 2015,
Cuzcatlan built a series of platforms at different levels, for stacking, placing, and compacting of dry tailings. The dry tailings are
transported by trucks from the tailings filter plant which is located at the mine processing area (Figure 18.1). Approximately two thirds of the production tailings are sent to the dry stack (finer portion of tailings), while the other one third (coarse
tailings) are treated in the paste backfill plant and sent back underground to the extracted mine workings as backfill.
A 300 g/m2
non-woven geo-textile lining was installed in the base of each platform to protect the 1.5 mm thick geo-membrane that covers the
entire basin. The design of the dry stack includes four construction phases (Table 18.1).
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Table
18.1 Volumes and life of the dry stack tailings facility
Stage |
Storage
Volume (m3) |
Dry
Stack life (years) |
Partial |
Accumulated |
Partial |
Accumulated |
Stage
1 |
431,000 |
431,000 |
1.17 |
1.17 |
Stage
2 |
655,000 |
1,086,000 |
1.77 |
2.94 |
Stage
3 |
500,000 |
1,586,000 |
1.37 |
4.30 |
Stage
4-N |
825,000 |
2,411,000 |
2.06 |
6.36 |
Stage
4-S |
1,622,000 |
4,033,000 |
4.56 |
10.92 |
The present
set of platforms provides a storage capacity of 4,033,000 m3 (Stages 1 to 4-S) with an elevation of 1,605 masl. Stage 4 construction
was completed in 2021 and the total capacity remaining is sufficient to cover the overall LOMP.
| 18.4 | Mine waste stockpiles |
The mine
as of the effective date of this Report has one waste stockpile used for storing waste material that could not be effectively disposed
of underground. This waste material does not generate acid water. The waste is generated mainly from mine development activities and
is not expected to increase significantly over the LOMP, unless some additional infrastructure or new mine areas are incorporated into
the Mineral Reserves. The stockpile stores 110,000 m3 of waste as of December 31, 2023, with a total capacity of 120,000 m3.
Cuzcatlan has the authorization to construct an additional waste stockpile, if required, that would increase total capacity to 200,000 m3,
sufficient for the LOMP.
The mine
currently has two ore stockpiles which store low-grade silver ore, or material pending evaluation (due to mixing of different ore types).
Once stockpile material of unknown grade has been sampled and results obtained, the geology department in coordination with the mine
and planning departments, takes the decision on whether to transport this material to the plant or to the waste stockpile.
| 18.6 | Concentrate transportation |
Tractor
trailers that can transport two 25 t containers each are used to transport concentrate. The containers must be made of stainless steel.
Each container is registered and weighed at the mine scales before the loading, sampling and weighing process is performed of the concentrate
prior to the unit being sealed and registered. The concentrate is then transported by road to the port of Veracruz in the State of Veracruz
for subsequent shipping to purchasers in 400 to 600 t lots.
The main
power supply to the mine is provided via a 115,000-volt circuit managed by the CFE, which has an operations switchboard next to the mine’s
principal substation.
The mine
also has a secondary reserve power supply in a 13,200-volt circuit, also managed by the CFE. This circuit is available to supply power
to critical equipment in case of power failure in the main circuit.
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| 18.7.1 | Principal substation |
The principal substation
of the mine consists of a 7 to 8 MVA transformer with a transformation ratio of 115 to 13.8 kV, connection-disconnection elements, and
protection relays.
Power distribution is primarily
through the use of overhead transmission lines on concrete posts. The basic distribution scheme is a 13,800-volt circuit via substations.
Power supply for the underground
portion of the mine consists of two circuits with the following arrangements:
| · | Overhead
network that feeds three transformers at surface with a transformation ratio of 13,800 to
440 volts with capacities of 750 kVA (2 pieces). |
| · | Overhead
network that feeds two transformers at surface with a transformation ratio of 13,200 to 4,160
volts with capacities of 1,500 kVA and 2,000 kVA. This is the principal network and has a
three-circuit distribution to the underground mine: |
| o | Circuit
1 - Transformer 1.1, located at surface with a transformer ratio of 13,800 to 4,160 volts
and a capacity of 2 MVA. This main transformer feeds the northern portion of the mine with
the following distribution: |
| § | Substations
#9, #23 and #24 at 1225 level with a transformer ratio of 4,160 volts to 480 volts all of
them are 1000 kVA which feeds the construction activities for the exploration drifts at this
level (BP084N, Stope Q and CX5G1). |
| § | Substation
#19 at 1100 level with a transformer ratio of 4,160 volts to 480 volts of 1000 kVA which
feeds all the operations power needs for the 1100 level (Stope R, Workshop 30). |
| § | Substation
#5 at 1100 level, with a transformer ratio of 4,160 volts to 480 volts of 500 kVA which supplies
power to a pumping station and drilling activities. |
| o | Circuit
2, comprises a high voltage cable of 13,800 volts connected to a cell with protection relay
and fed from surface to the 850 level in the northern sector of the mine with the following
distribution: |
| § | Substation
at 1350 level with a transformer ratio of 13,800 volts to 480 volts of 1,000 kVA which feeds
all the operational power needs for the main 250,000 cfm fan and Stope P |
| § | Substation
# 18 at level 1000, with a transformer ratio of 13,800 volts at 480 volts of 1,000 kVA which
feeds all the operational power requirements for the 1000 level station pump #5 |
| § | Substations
#21 and #22 at level 900 and 850 respectively both with a transformer ratio of 13,800 volts
at 480 volts of 1,000 kVA which feeds all the operational power requirements for the deepest
place of the mine. |
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| o | Circuit
3, located at surface with a transformer ratio of 13,800 to 4,160 volts with a capacity of
1.5 MVA. This main transformer feeds the central side of the mine with the following distribution: |
| § | Substation
# 4 at 1300 level, with a transformer ratio of 4,160 volts to 480 volts of 750 kVA which
feeds the main 120,000 cfm fan and pumping system 2. |
| § | Substation
#6 and #16 at 1200 level, with a transformer ratio of 4,160 volts to 480 volts of 750 kVA
and 1000 KVA respectively which feeds the operational demands of the 1200 level and the second
250,000 CFM fan. |
| § | Substation
# 10 at 1100 level, with a transformer ratio of 4,160 volts to 480 volts of 1,000 kVA which feeds the operational |
|
|
demands of the 1100 level as well as the ventilation for the exploration drift. (Stope W, Stope V, BP777). |
| o | Circuit
4, transformer 1.3 13,800 v / 440 v 750 kVA (2 pieces), these transformers feed the compressors
at surface, contractor offices and the training area of the mine safety brigade. |
| 18.8 | Communications systems |
Communications
services are supplied by Teléfonos de México S.A.B. de C.V. (Telemex). The communication infrastructure is based on an
optical fiber link to the mine’s data center providing internet bandwidth at a synchronous link of 70 Mbps. The San Jose Mine has
an air-conditioned data center, with controlled access and close circuit television. The structures cabling network is Category 6.
Phone communications
are provided by Telemex via an E1 connection with 10 digital phone lines enabled. The telephone switching equipment uses internet protocol
(IP) connectivity with 90 extensions.
The underground
mine communication network is operated using an optical radio backbone. Based in this backbone, there is an array of very high frequency
(VHF) radio repeaters to provide radio communications. Underground facilities have three VHF channels, one for operators, another for
traffic in the main ramp, and the last for rescue services. The coverage is approximately 11 km.
In addition,
the mine operates a personal detection system, based on radio frequency identification technology. This has seven detection points on
the surface and thirty detection points underground, with coverage of the major workings of the mine. The purpose of this system is to
identify and monitor personnel movement inside the mine in real time for safety purposes.
Cuzcatlan
has implemented a video surveillance system at the mine, which consists of 124 cameras with the purpose of monitoring both surface and
underground facilities including the main pump stations, power stations and meeting points.
Some areas
of the underground mine have access to voice and data services which include nine IP phone lines as well as local networks with internet
service to two meeting areas located on level 1200 and 1000, the maintenance workshop, and the explosive warehouse.
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| 18.9 | Comment on Section 18 |
The QP
considers that the infrastructure required to support the LOMP is in place and is operational.
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| 19 | Market
Studies and Contracts |
The San
Jose Mine is an operating mine with concentrate sales contracts in place for 2024. As a result, market studies are not relevant to the
operation.
Since the
operation commenced commercial production in September 2011 a corporate decision was made to sell the concentrate on the open market.
In order to get the best commercial terms for the concentrates, it is Fortuna’s policy to sign contracts for periods no longer
than one year. In 2023 Cuzcatlan agreed to a short-term contract to sell concentrate to Trafigura PTE LTD (15,000 t) and Arrow Metals
(15,000t) for 12 months. Once this contract expires in 2024 a new contract will be negotiated.
Silver
and gold payment terms are typical within the industry. Concentrate that contains fluorine in excess of the specification range is subject
to a penalty that is negotiated with the buyer dependent on the delivered fluorine level.
All commercial
terms entered between the buyer and Cuzcatlan are regarded as confidential but are considered to be within standard industry norms.
| 19.2 | Commodity price projections |
The Fortuna
financial department provides Cuzcatlan with metal price projections to be used in their analysis and as used in the Report. Fortuna
established the pricing using a consensus approach based on analyst and bank forecasts prepared in May 2023.
The QPs
have reviewed the key input information and consider that the data reflect a range of analyst predictions that are consistent with those
used by industry peers. Based on these sources, price projections are considered acceptable as consensus prices for use in mine planning
and financial analyses for the San Jose Mine in the context of this Report.
A long-term
price estimate of US$23.90/oz for silver and US$1,880/oz for gold has been applied, based on mean consensus prices for 2024.
Cuzcatlan
has used a Mexican peso exchange rate of 19 pesos to the US dollar for financial analysis purposes, which conforms with general industry-consensus.
| 19.3.1 | Silver–gold concentrate |
Trafigura
and Arrow Metals have stipulated the specifications for silver-gold concentrate delivered from Cuzcatlan for 2023 and 2024, which are
regarded to be within standard industry norms.
Fluorine,
zinc, and lead are deleterious elements that needs management at the San Jose Mine.
Cuzcatlan
has 14 major contracts for services relating to operations at the mine regarding: mining activities, ground support, raise boring, drilling,
transportation, electrical installations, plant and mine maintenance, explosives and civil works. The costs of such contracts are accounted
for in the capital and operating expenditure depending on work
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performed. Contracts are negotiated and renewed as needed. Contract terms
are typical of similar contracts in Mexico that Fortuna is familiar with.
| 19.4 | Comment
on Section 19 |
The QPs
have reviewed the information provided by Fortuna on marketing, contracts, metal price projections and exchange rate forecasts, and note
that the information provided is consistent with the source documents used, and that the information is consistent with what is publicly
available on industry norms. The information can be used in mine planning and financial analyses for the San Jose Mine in the context
of this Report.
Long-term
metal price assumptions used in the Report are based on a consensus of price forecasts for those metals estimated by numerous analysts
and major banks. The analyst and bank forecasts are based on many factors that include historical experience, current spot prices, expectations
of future market supply, and perceived demand. Over a number of years, the actual metal prices can change, either positively or negatively,
from what was earlier predicted. If the assumed long-term metal prices are not realized, this could have a negative impact on the operation’s
financial outcome. At the same time, higher than predicted metal prices could have a positive impact.
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| 20 | Environmental Studies, Permitting
and Social or Community Impact |
The environmental
information presented in this Report is derived from Cuzcatlan’s environmental impact studies, land use changes, permits, licenses
and environmental studies.
| 20.2 | Regulation
and permitting |
In 2006,
Cuzcatlan began exploration activities using drilling and underground exploration of the Trinidad and Bonanza veins. Studies and reports
were submitted to the Ministry of Environment and Natural Resources, and authorizations SEMARNAT-SGPA-DIRA-179-2007, SEMARNAT-SGPADIRA-366-2007
and SEMARNAT-SGPA-DIRA-896-2008 were granted.
During
2008, an Environmental Impact Statement was submitted to the SEMARNAT Delegation in the State covering the underground ramp and initial
mine development. This was approved in 2009 through SEMARNAT-SGPA-DIRA-1731-2009.
| 20.2.1 | Environmental legislation |
The key
environmental legislation applicable to the San Jose Mine is as follows:
| · | General
Law of Ecological Equilibrium and Environmental Protection and its regulations. |
| · | General
Law for the Prevention and Integral Management of Waste and its Regulations. |
| · | General
Law on Climate Change and its Regulations. |
| · | General
Law of Wildlife and its Regulations. |
| · | National
Water Law and its Regulations. |
| · | Mexican
Official Standards. |
| 20.2.2 | Environmental obligations |
Cuzcatlan
must comply with the terms and conditions of the authorizations it has acquired in the different project phases in terms of environmental
impact, change of land use, licenses and permits, as well as compliance with the prevention and mitigation measures established in each
of the environmental studies.
Cuzcatlan
has adhered to the Global Industry Standard on Tailings Management as of December 2022, and is committed to work on its implementation.
The company also became ISO 14001 certified in May 2021.
The key
permits that have been granted to Cuzcatlan and which support its establishment and operation are as follows:
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| · | Environmental
Impact Authorization, issued under official communication No. SEMARNAT-SGPA-DIRA-1731/2009,
through which SEMARNAT authorized the construction, execution and maintenance of the San
José mining unit, for a period of 12 years, effective until October 23, 2021,
over a surface area of 92.00 ha. In 2021 SEMARNAT authorized the term extension for 12 additional
years. (EIA Extension). Information on the dispute with SEMARNAT over the permit duration
is provided in Section 4.4. |
| · | Despite
the above, on January 28, 2022, the Company received a notice (the Resolution SEMARNAT-SGPA-DIRA-367/
2011, through which SEMARNAT issued an environmental impact authorization for the modernization,
operation and maintenance of the wastewater treatment plant in Ocotlán de Morelos,
Oaxaca (PTAR Ocotlán), effective until May 13, 2031. Cuzcatlan is the manager
of this permit in accordance with the agreement with the municipality of Ocotlan de Morelos. |
| · | Resolution
SEMARNAT-SGPA-DIRA-173-2010, through which SEMARNAT authorized project “Construction
and installation of a water intake and conduction work for Industrial Use, effective until
March 2030. |
| · | Resolution
SEMARNAT-SGPA-UGA-1067-2015, authorized the project “Construction dry stack of the
tailing, in San José del Progreso, Oaxaca”, effective until March 2026. |
| · | Resolution
SEMARNAT-SGPA-UGA-0901/2017, through which SEMARNAT authorized project “Expansion Dry
stack tailing” effective until September 2031. |
| · | Resolution
SGPA/DGIRA/DG/01115, through which DGIRA authorized project “Third expansion dry stack
tailing”, effective until February 2028. |
| · | Resolution
SGPA/DGIRA/DG-06101-21, through which DGIRA authorized project “Actualización
de Obras y Actividades” effective until December 2033. |
| · | Resolution
20-PMG-I-1876-2015, through which DGGIMAR, in which the hazardous waste management plan set
out. |
| · | General
permit No. 4184, issued by National Defense for the use of explosives in the mine’s
activities. This permit must be renewed annually. |
| · | Agreement
between the municipality of Ocotlán de Morelos and Cuzcatlan, permitting Cuzcatlan
to operate the wastewater treatment plant located in Ocotlán de Morelos, Oaxaca, effective
until January 1, 2025. |
| 20.3 | Environmental
baseline |
The San
Jose Mine has a semi-arid or semi-warm climate with summer rains, which, based on the climate classification developed by W. Köeppen,
modified by Enriqueta García (García, 2004), has the climatic formula BS1hw (w). The average annual temperature varies
between 18 and 22 °C and rains in summer. Total annual precipitation ranges from 400 to 800 mm. There are two high rainfall periods,
one in June and a second in September.
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Cuzcatlan
monitors air quality by measuring total suspended particulate matter, particles smaller than 10 µm and smaller than 2.5 µm,
on a quarterly basis by an external laboratory accredited by the Mexican Accreditation Entity and approved by the Federal Environmental
Protection Agency.
Cuzcatlan
monitors surface and groundwater quality on a quarterly basis through an external laboratory accredited by the Mexican Accreditation
Entity and approved by the National Water Commission. The results obtained for surface and groundwater quality indicate that the water
is of good quality; no impact from mining activity has been identified.
Surface
The San
Jose Mine is located within Hydrological Region Number 20 (HR 20) Costa Chica de Guerrero. This hydrological region is an irregular pentagon
in shape, elongated in the east–west direction. The hydrological region covers approximately 24.4 km2. HR 20 is divided
into three watersheds: Atoyac River, Arena River and others, and Ometepec or Grade River. The mining operations are located within the
Atoyac River watershed (INEGI, 2004).
Groundwater
The Mine
area is located within the Valles Centrales Aquifer, located in the central portion of the state of Oaxaca.
The dominant
and most important soil types for the San José Mining Unit are Feozem, Leptosol and Luvisol.
The fauna
identified in baseline studies include opossums, armadillo, rabbit, squirrel, lynx, yaguarundi (wild cat), gray fox, coyote, weasel,
skunk, cacomixtle, tejon, and racoon. Only three species are listed in some category of protection under the Mexican Official Standard
NOM-050-SEMARNAT-2010, the yaguarundi and cacomixtle are listed as endangered and the species Herpailurus yaguarundi and lynx
are listed as CITESM endangered.
Vegetation
is made up of a mosaic of scrub and some scattered trees. The most dominant thickets consist of Acacia farnesiana and Heliocarpus
terebinthinaceus followed sporadically by Ipomoea murucoidesm bursera glabrifolia and Bursera bipinnata. Of the 68
flora species found in the study area, only one is listed in NOM-059-SEMARNAT-2010 (Echinocactus platyacanthus), for which there
is a special protection and management program.
The site
is degraded due to the severe pressure on the soil from goat ranching and rain-fed agriculture. Vegetation originally covered less than
20 % of the surface area.
| 20.3.7 | Ecosystem characterization |
The environmental
impact and land use change studies for the San Jose Mine include a description of the ecosystem at the site, and the description includes
the different stages of the project, such as exploration, construction, operation, closure and post-closure.
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The characterization of the local ecosystem has
been described in each of the environmental impact and land use change studies that have been carried out during the different stages
of the San Jose Mine development.
| 20.3.8 | Protected
areas and archaeology |
There are no protected natural areas declared
by the country's environmental regulations in the San Jose Mine area. No archaeological sites were identified during the preparation
of the baseline environmental studies in the San Jose Mine area.
| 20.3.9 | Environmental
risks and management plan |
No significant environmental risks were identified
in the environmental baseline studies. During the operation stage, environmental risks and mitigation measures for the operation stage
are determined on an annual basis.
Cuzcatlan has an environmental management and
monitoring plan that includes follow-up on environmental programs for flora and fauna management, management of urban solid waste, special
waste, hazardous waste, and mining waste, as well as a surface and groundwater monitoring plans, environmental noise monitoring, monitoring
of the survival rate of flora included in reforestation programs, and a wildlife monitoring plan.
Sustainability indicators have also been defined
and their performance monitored monthly. The sustainability indicators defined at the San Jose Mine are as follows:
| · | Fresh
water consumption rate (m3/t). |
| · | Energy
consumption rate (Gj/t). |
| · | Dry
lime deposition rate in dry Stack (t of dry lime/t of ore processed). |
| · | GHG
generation rate (tCO2eq/kt). |
| 20.3.10 | Environmental
areas of focus |
The most important areas of environmental interest
for Cuzcatlan are compliance with the following:
| · | Compliance
with national and international regulatory requirements. |
| · | Compliance
with environmental monitoring programs. |
| · | Compliance
with the environmental training plan. |
| · | Maintaining
the certification of the environmental management system based on ISO 14001:2015. |
| · | Compliance
with corporate environmental requirements. |
| 20.3.11 | Operations and management |
The protection of the environment is a priority
for Cuzcatlan in each of its activities and processes. The Company has identified environmental aspects that could be impacted by its
activities in the areas of exploration, mineral beneficiation, maintenance, mining and support. For each of the areas, appropriate controls
have been established to prevent and mitigate significant environmental risks and impacts associated with these activities.
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In 2022, Cuzcatlan obtained certification in
environmental and safety management systems aligned with ISO 14001:2015 and ISO 45000:2018.
| 20.4.1 | Socioeconomic
and cultural aspects |
The mining area occupies a total area of 92.01
ha, divided into two polygons (north and south) within which an area of 16.88 ha is occupied for industrial operations.
To better understand the environment around the
mine and establish priorities for social attention, the areas of direct and indirect influence were identified within an approximate
radius of 5 km.
Within the area of direct influence, as of 2020
there were 11,215 inhabitants in the localities of the following municipalities.
| · | Municipality
San Jose del Progreso: Arroyo Salado, El Cuajilote, El Jaguey, El Porvenir, La Alianza,
Los Cedros, Los Díaz, Los Patino, Maguey Largo, Minerales de Oaxaca y San Jose del
Progreso. |
| · | Municipality
Ejutla: La Noria de Ortiz y Monte del Toro |
| · | Municipality
San Martín de los Cansecos: Colonia Benito Juarez y Barrio Emiliano Zapata |
| · | Municipality
Magdalena de Ocotlan: Magdalena de Ocotlan. |
An area of indirect influence has also been identified
with 8 localities where Cuzcatlan maintains a positive relationship. These localities are as follows:
| · | Municipality
of San Pedro Apostol: Colonia Guadalupe, Los Tres Hermanos and San Pedro Apostol. |
| · | Municipality
of San Jose del Progreso: Rancho Los Vásquez, La Chilana, San Jose La Garzona,
El Mogote and La Labor Grande. |
This area of influence of the San Jose Mine coincides
with the "Central Valleys indigenous region", according to the National Commission for the Development of Indigenous Peoples.
The towns in the area of influence comprise a total of 1,924 people that are considered indigenous.
The political organization of these localities
is diverse. The town halls have a municipal president as a political-administrative figure, who, in turn, relies on figures considered
auxiliary authorities, in this case Municipal Agents and Police Agents.
In addition, the “ejido’’ is
constituted by a legally registered assembly, who are represented by the “ejido’’ commissioner. It is important to
mention that the municipality of San Jose del Progreso has “ejido’’ or communal lands, but they do not have an “ejido’’
commissioner that represents them.
The main economic activities in the area of influence
are primary agriculture and livestock. There are also other activities such as crafts and textile maquiladora. Secondary activities include
mining, construction and power generation and supply. Tertiary activities include tourism, commerce, and some basic services such as
domestic services.
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Festivities that commemorate patron saints are
major cultural events. Community members and groups participate in this activity to annually celebrate township foundation.
The most basic educational levels are found in
the towns of Barrio Emiliano Zapata, Colonia Benito Juárez, Los Díaz and San José La Garzona, where education does
not exceed fifth and sixth grade elementary school level.
Only 63 people in the area were classified as
unemployed.
There is easy access to transportation routes
such as highways and roads. Schools and non-specialized medical centers are also available.
| 20.4.2 | Stakeholder
engagement |
Since the beginning of the first exploration
activities at San Jose, there has been interaction and engagement activities with the main stakeholder groups.
The main stakeholders of interest were initially
identified as the municipalities and the auxiliary and agrarian authorities. Social and political organizations, as well as State and
Federal officials, also play an important role.
Cuzcatlan has been identifying and collaborating
with various community groups and stakeholders.
Due to the history of social issues in the Oaxaca
region, it has been essential for Cuzcatlan to accurately identify the main leadership groups, and to consistently work with them to
establish and maintain a healthy relationship between Cuzcatlan and the communities.
The current key stakeholder groups are presented
in Table 20.1.
Table 20.1
Main stakeholder groups at the San Jose Mine
Group |
Description |
Relationship |
Local
Governments |
Members
of the current governments in the municipalities of the area of influence. |
Each
municipality within the area of influence have different interests and collaboration agreements. |
Owners
of land under occupation |
Owners
of properties where the company has temporary occupation for operating activities. |
Formal
agreements are maintained with these people to guarantee the legal and proper use of each property. |
Citizens
Committee |
Group
of people, who since the beginning of mining activities, have facilitated communication with neighboring communities. |
With
this group, productive projects are carried out through social investment, infrastructure support and social development channels. |
Peasant
Group |
People
dedicated to the primary activities of the land. |
With
this group, productive projects are carried out through social investment, support is channeled for the development of agricultural
activities. |
Local
Suppliers |
People
who supply local services to the operation. |
Local
products and services are used to guarantee what is necessary for the operation and contribute to the economic development of the
area. |
COPUVO |
Social
organization created to manage social support in the region. Anti-mining group. |
Cuzcatlan
are currently collaborating with CUPOVO to channel social investment support, mainly in housing. This
new collaboration means a great advance of relationship because historically they have pronounced themselves as an anti-mining group. |
The radio program "Hablando
en Plata” is important as part of the Cuzcatlan’s social relations, as this is where information on the culture of San José
del Progreso and the Valles Centrales region is shared.
| 20.4.3 | Community
development |
Important investments have been made by Cuzcatlan
to contribute to the sustainable development of the neighboring communities.
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At each stage of the operation, various social
development strategies have been implemented based on the key areas of education, health, economy, culture, housing and social infrastructure.
The main objective of the education initiative
is to contribute to reducing the educational gap through the following programs and activities:
| · | Strengthening
workshops through the collaboration of education professionals on topics such as: life planning,
emotional control and youth leadership. |
| · | The
Cuzcatlan scholarships program that has been active since 2014 and allows students from San
Jose del Progreso and its agencies to continue their studies in upper secondary and higher
education. Currently there are 145 beneficiaries. |
| · | Agreement
with the State Institute of Adult Education (IEFA) of the State of Oaxaca, has allowed the
education coverage for the adult population to be expanded and that they continue with their
life plan to complete their basic studies. Education is standardized at the primary, secondary
and high school levels. |
| · | Contribution
of equipment for schools including materials and supplies to improve the conditions of the
educational institutions of the municipality. |
Cuzcatlan has implemented actions to directly
contribute to the areas of prevention, care and community health infrastructure through the following programs or activities:
| · | Medical
materials for homes and community health centers. |
| · | Payment
of medical fees for the expansion of medical care in the clinic of the municipal of San Jose
del Progreso. |
| · | Setting
up of an emergency fund for the COVID-19 pandemic in conjunction with the San Jose del Progreso
city council and the Oaxaca State Health Secretariat. |
| · | Maintenance
of ambulances for municipal transfers. |
| · | Delivery
of medicines for basic medical conditions to homes and community health centers. |
| · | Basic
food package endowments twice a year. |
| · | Mental
health care for the local applicable population. |
| · | Healthy
home program to benefit the population that has deficiencies in essential housing facilities
(bedroom, kitchen) with construction materials and follow-up to improve housing spaces. |
| · | Donations
for medical expenses, surgeries and medications for special health cases and situations. |
| · | Prevention
workshops and talks through collaboration with experts in health issues. |
| · | Funeral
service programs that support donations in kind for funeral expenses. |
Investments are made to grow productive activities
in the operational area of influence. Cuzcatlan’s main programs include:
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| · | Contributions
for the promotion of agricultural and productive investments with “ejidatario”
peasants. Since the establishment of this agreement, the group has contributed to the development
of its agricultural activities. |
| · | Equipment
for businesses or local ventures. |
| · | Contribution
to artisan ventures (production of textile garments and embroidery). |
| · | Construction
of greenhouses for tomato production. |
| · | Local
supplier support with training and partnerships considered for the supply of products and
services. All opportunities that Cuzcatlan offer for local businesses are constantly reviewed. |
| · | Job
creation: Currently, more than 70 % of the jobs generated at the operation are for people
from the mine’s area of influence. |
Cuzcatlan has been a leader in the investment
and management of social infrastructure projects, contributing to numerous investments in roads, schools, streets, public spaces, public
lighting, among others. Key activities include:
| · | Roofs
for civic squares. |
| · | Purchase
and installation of public lighting. |
| · | Construction
of paved streets. |
| · | Construction
and repair of schools. |
| · | Construction
of civic squares. |
| · | Construction
of rain channels. |
| · | Rehabilitation
of roads. |
| · | Extensions
of community drainage. |
| · | Construction
of retaining walls. |
| · | Construction
of perimeter fences. |
| · | Donation
of pipes for water distribution. |
| · | Contribution
for rehabilitation of dump. |
| · | Construction
of infrastructure for water collection. |
| 20.5.1 | Legal
requirements and other obligations |
The main applicable national standards for mine
closure and the safeguarding of mining works and operations correspond to the following Mexican Official Standards and Regulations:
| · | General
Law of Ecological Equilibrium and Environmental Protection (LGEEPA) |
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| o | LGEEPA
defines restoration as the "set of activities aimed at recovering and reestablishing
the conditions that favor the evolution and continuity of natural processes". |
| · | Federal
Law of Environmental Responsibility (LFRA) |
| o | Article 13
of the LFRA states that "The reparation of damages caused to the environment will consist
of restoring habitats, ecosystems, natural elements and resources, their chemical, physical
or biological conditions and the interaction relationships between them, as well as the environmental
services they provide, by means of restoration, reestablishment, treatment, recovery or remediation". |
| · | Mining
Law Article 27.- The holders of mining concessions, regardless of the date of their
granting, are obliged to: |
| o | IV.
Subject themselves to the general provisions and to the Mexican official standards applicable
to the mining-metallurgical industry regarding safety in mines and ecological balance and
protection of the environment. |
| o | Article 39.-
In the activities of exploration, exploitation and benefit of minerals or substances, the
mining concession holders must take care of the environment and ecological protection, in
accordance with the legislation and regulations of the matter. |
Other general regulations applicable to mine
closure, referring to Mexican Official Standards of reference for mine restoration and closure are as follows.
| · | NOM-120-SEMARNAT-2020,
which establishes environmental protection specifications for direct mining exploration activities. |
| · | NOM-138-SEMARNAT-2012,
which establishes the maximum permissible limits of hydrocarbons in soils and guidelines
for sampling in the characterization and specifications for remediation. |
| · | NOM-147-SEMARNAT/SSA1-2004,
which establishes the criteria for determining remediation concentrations of soils contaminated
by arsenic, barium, beryllium, cadmium, chromium, hexavalent, mercury, nickel, silver, lead,
selenium, thallium and/or vanadium. |
| · | NOM-001-SEMARNAT-1996,
which establishes the maximum permissible limits for contaminants in water discharges into
national waters and property. |
| · | NOM-141-SEMARNAT-2003,
which establishes the procedure for characterizing tailings, as well as the specifications
and criteria for the characterization and preparation of the site, project, construction,
operation and post-operation of tailings dams. |
| 20.5.2 | Mine
closure management |
Cuzcatlan's restitution and closure plan contemplates
the following zones:
| · | Industrial
zone, in the north polygon, which includes the stockpile, crushing, grinding, flotation,
tailings thickening, maintenance shop, minor workshops, concentrates, roads and parking areas. |
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| · | Mine
zone, in the north polygon, which includes the mine access ramp, shafts, pits, hydraulic
backfill, tailings filtering plant, ore stockpiles, roads, parking areas, mine services,
and scales. |
| · | Auxiliary
and complementary work zone, in the north polygon, separated into four areas that include
administrative offices, warehouses, services, recreational area, soil storage, pools, powder
magazines, contractors’ yard, CFE substation, roads and road surfaces. |
| · | Territorial
reserve zone, in the north polygon, consists of areas with secondary vegetation, relicts
of primary vegetation, mine farm, rainwater control lagoon, mine nursery, and reforestation
areas. |
| · | Tailings
zone, in the south polygon, comprising tailings dam, dry tailings deposit, soil stockpile,
water recovery ponds, diversion channel, parking and contractor areas, roads and land with
secondary and primary vegetation, as well as portions degraded by previous agricultural activities. |
| · | Private
land closure zone, consisting of Cuzcatlan's social commitment to close the existing mine
shafts and mine entrances related to old mining activities. |
The final stage of the San Jose Mine, assuming
the timely implementation of progressive closure actions on land surrounding the operations and works that have fulfilled their useful
life or design capacity (such as dams), will focus on the following:
| · | Final
inventory of equipment, materials and resources, considering not only industrial aspects
but also a detailed balance of fill material and conformation of the tailings dam, anticipating
the possibility of using dry tailings (non-hazardous and inert) as a supply of fill material
or by using the dry tailings deposit as a bank of material for filling the dam pond. |
| · | Prepare
a closure priority plan to eliminate expendable facilities and conserve those that will serve
as support during reclamation and closure activities (utilities, control house, electricity,
water, adequately sized parking for machinery, offices and temporary warehouses, etc.). |
| · | Carry
out the dismantling of machinery to be reused (relocation) or auctioned, including the stockpiling
of usable materials for closure purposes (construction of grids, mine support materials,
foundations for backfill, sign supports, posts, etc.). Dismantling should be based on
a study that considers the appraisal of equipment and materials, as well as the execution
procedure for safeguarding the value and estimation of the recovered value. |
| · | Execute
salvage of recyclable, saleable materials or with potential to be used by the local communities
(beams, scrap metal, pipes, sheets, warehouses, etc.). |
| · | Demolition
of cement and concrete structures, preferably with crushing that provides adequate characteristics
for usage in the stabilization of other works (mine backfill and construction of mine cap
or mine seal/shafts/ramps). |
| · | If
required by final inspections and surveys, carry out complementary stabilization of tailings
dams and, in the case of mine accesses, ensure their stability (elimination or management
of subsidence risk, if applicable). |
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| · | Application
of salvaged organic soil and soil decompaction in embankments, yards and parking lots by
scarification. |
| · | Execute
reforestation works based on nursery plants. |
| · | Installation
of temporary restriction zones to encourage natural restitution, as well as to protect the
restored areas during the monitoring and maintenance period. |
| · | Installation
of permanent restriction zones for conservation purposes and as an additional security measure. |
| · | Return
or restitution of basic conditions of the land to sustain flora, fauna, restitution of environmental
services and in general, carry out an ecological restoration to a self-sustainable space
in the medium and long term. |
| · | Achieve
final approval and/or social license to exit, so that both the community and Cuzcatlan comply
with the closure objectives and local development expectations. |
| 20.5.3 | Reclamation
and closure of affected areas |
The 2022 updated Cuzcatlan reclamation and closure
plan used the zone grouping, structures and buildings as a starting point for reclamation and closure plan budgeting.
The steps applicable to restoration are presented
in sequential order as follows:
| · | Dismantling
of all salvageable equipment, machinery and structures for salvage, relocation, sale, reuse
or recycling as scrap. |
| · | Demolition
of both buildings and foundations, including patio and parking lot siding slabs not proposed
to remain in place at the abandonment stage. |
| · | Scarification
of compacted layers of soils on land used as yards, material deposits, buildings and as physical
preparation of the land for the execution of reforestation works. |
| · | Filling
and sealing of mines. |
| · | Covering
of tailings dam and dry tailings facility and land stabilization. |
| · | Completion
of additional studies and surveys for closure purposes (geotechnical, geochemical, future
land use. |
| · | Maintenance
to carry out repair or improvement in the first years immediately following land and site
closure. |
| 20.5.4 | Monitoring
during closure |
The San Jose Mine 2022 updated restitution and
closure plan will require constant monitoring to ensure the closure plan objectives are met.
Monitoring will include:
| · | Inspections
and evaluations. |
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| · | Monitoring
of environmental conditions with respect to quantitative and semi-quantitative variables
through annual or semiannual sampling as required. |
| · | Reporting
of sampling and monitoring results. |
Meetings or assemblies with the community and
local authorities will be scheduled on a regular basis to:
| · | Provide
a space where they can freely express their perspectives and opinions on the end of operation
and mine closure. |
| · | Report
on restoration performance and partial results of the monitoring stage. |
| · | Ensure
land use for conservation purposes and detect any possible deviation/interest in the land. |
| 20.5.5 | Monitoring
post closure |
It is estimated that the zones will be monitored
for a period of five years after the abandonment of the works, depending on the conditions in which the site is abandoned. The monitoring
period may vary depending on the findings of the relevant regulator completing closure evaluations.
The mine plan anticipates closure of the operation
in late 2024. The Company has assigned a dedicated team to review and update a multiyear progressive mine closure and monitoring plan
with a current estimated budget of US$ 27 million, which will begin its implementation during 2024. Multiple considerations are being
included such as closure-related technical studies and designs, remediation of affected areas, decommissioning and removal of infrastructure,
landform reshaping, revegetation, and value-added activities for the communities associated with progressive closure, repurposing, and
where appropriate, long-term monitoring and maintenance, whilst adhering to strict compliance with mine closure governmental regulations
and high international standards.
| 20.6 | Greenhouse
gas (GHG) emissions |
In 2022, Cuzcatlan had a GHG emission estimate
of 43,516 tCO2eq. In the same year Cuzcatlan began installing solar cells in offices, a dining room, laboratory and general
warehouse to generate clean energy and contribute to initiatives to mitigate climate change.
In 2023, Cuzcatlan continued to carry out activities
to mitigate climate change, such as changing fluorescent lamps for light-emitting diode lamps in general offices and the underground
mine and working on the classification of urban solid waste and special handling waste so that they can be used in industrial processes
as part of their raw material.
Cuzcatlan is also working to find alternatives
for saving energy, water and minimizing waste generation.
| 20.7 | Comment on Section 20 |
It is the opinion of the QPs that the appropriate
environmental, social and community impact studies have been conducted to date for the San Jose Mine. Cuzcatlan has maintained all necessary
environmental permits that are prerequisites for the operation of the mine infrastructure and the maintenance of mining activities. Closure
costs have been estimated at US$ 27 million and a five-year post closure monitoring period is envisaged.
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21 | Capital and Operating Costs |
The San Jose Mine is a producing operation managed
by Cuzcatlan and has been mined as an underground operation continuously since September 2011. Capital and operating cost estimates
are based on the established cost experience gained from the operation, projected budgets, and quotes from manufacturers and suppliers.
Overall, the cost estimation is of sufficient detail that, with the current experience at Cuzcatlan, Mineral Reserves can be declared.
| 21.1 | Sustaining
capital costs |
As the mine has entered its last planned year
of operation, sustaining capital expenses such as mine development meters, infill drilling, mine equipment and other necessary expenses
have been considered as part of operating costs and covered by the projected cash flow generation in 2024.
Projected operating
costs for the LOMP are detailed in Table 21.1.
Table 21.1 Summary of projected operating
costs in 2024
Area |
Units |
Q1 |
Q2 |
Q3 |
Q4 |
Total |
Mine |
US$/t |
60 |
56 |
43 |
39 |
48 |
Plant |
US$/t |
29 |
29 |
20 |
19 |
23 |
Indirect |
US$/t |
31 |
31 |
21 |
19 |
24 |
Distribution |
US$/t |
8 |
9 |
7 |
7 |
8 |
Community
Relations |
US$/t |
5 |
6 |
4 |
3 |
4 |
Sustaining
Capital expenses |
US$/t |
15 |
24 |
10 |
6 |
12 |
Total |
US$/t |
148 |
155 |
104 |
93 |
120 |
The projected operating costs are based on the
current mining and processing requirements for 2024, as well as historical information regarding performance, operational and administrative
support demands.
Operating costs include site costs and operating
expenses to maintain the operation. These operating costs are analyzed on a functional basis and the cost structure can differ from the
operating costs reported by the financial statements published by Fortuna.
Site cost activities performed at the property
include mine, plant, indirect and distribution of the commercial products. Community relations and capital expenditure costs are projected
to be covered by Cuzcatlan’s cash flows in 2024. Brownfields exploration costs executed at the site are planned to be paid by Fortuna’s
cash flows from its four other operating mines.
The Company has assigned a dedicated team to
review and update a multiyear progressive mine closure and monitoring plan with a current estimated budget of US$ 27 million, which will
begin its implementation during 2024. Multiple considerations are being included such as closure-related technical studies and designs,
remediation of affected areas, decommissioning and removal of infrastructure, landform reshaping, revegetation, and value-added activities
for the communities associated with progressive closure, repurposing, and where appropriate, long-term monitoring and maintenance, whilst
adhering to strict compliance with mine closure governmental regulations and high international standards.
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| 21.3 | Comment on Section 21 |
The capital and operating cost provisions for
the LOMP that supports Mineral Reserves have been reviewed. The basis for the estimates is appropriate for the known mineralization,
mining and production schedules, marketing plans, and equipment replacement and maintenance requirements.
The QP considers the costs estimated for the
San Jose Mine as reasonable based on industry-standard practices and actual costs observed for 2023 and the production for the projected
year 2024.
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Fortuna is using the provision for producing
issuers, whereby producing issuers may exclude the information required under Item 22 for technical reports on properties currently in
production and where no material production expansion is planned.
The global after-tax financial results exhibit
a negative outcome when factoring in exploration costs and the total mine closure cost. However, the projected financial outcome for
2024, considering only operational costs, shows a positive result. Fortuna expresses its commitment to covering Brownfields exploration
costs for 2024 and the subsequent expenses upon cessation of mining operations using funds derived from corporate profits. Given this,
the QP believes it is reasonable to continue mining operations throughout the planned operational period in 2024 to alleviate the negative
financial and social results of mine closure and support the current Mineral Reserve declaration under two assumptions:
| · | Fortuna
will cover the mines Brownfields exploration and closure costs at the corporate level. |
| · | Adequate
financial support is secured from Fortuna's other mining units, which, as per plans, will
be operational until 2035 and are expected to generate sufficient proceeds to cover closure
costs at San Jose. |
| 22.2 | Comments on Section 22 |
An economic analysis
was performed in support of the estimation of the Mineral Reserves; this indicated a positive cashflow for the period set out
in the LOMP using the assumptions detailed in this Report excluding closure costs and brownfields explorations that will be covered by
Fortuna.
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This section is not relevant to this Report.
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24 | Other Relevant Data and Information |
This section is not relevant to this Report.
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25 | Interpretation and Conclusions |
| 25.1 | Mineral
tenure, surface rights, water rights, royalties and agreements |
Fortuna was provided with a legal opinion that
supports that the mining tenure held by Cuzcatlan for the San Jose Mine is valid and that Fortuna has a legal right to mine the deposit.
Tenure is held in the name of Cuzcatlan with
all mining concessions having an expiry date beyond the expected mine life.
The San Jose Mine is not subject to any back-in
rights, liens, payments or encumbrances. Mineral Reserves have the following royalties payable:
| · | There
is a 1.5 % royalty to Maverix on the Reduccion Taviche Oeste concession. |
| · | There
is a 3 % royalty on the Progreso concession and a 1 % royalty the Reduccion Taviche Oeste
concession payable to SGM. |
Cuzcatlan has signed 45 usufruct contracts with
landowners to cover the surface area needed for the operation and tailings facilities, which have been registered before the National
Agrarian Registry. Surface rights are granted for between 10 and 30 years with the ability to extend the contracts if required. These
agreements provide sufficient rights for the remaining LOMP.
| 25.2 | Geology
and mineralization |
The San Jose Mine area is underlain by a thick
sequence of sub-horizontal andesitic to dacitic volcanic and volcaniclastic rocks of presumed Paleogene age. These units have been significantly
displaced along major north and northwest-trending extensional fault systems with the precious metal mineralization being hosted in hydrothermal
breccias, crackle breccias, and sheeted stockwork-like zones of quartz/carbonate veins emplaced within zones of high paleo permeability
associated with the extensional structures.
The mineralized structural corridor extends for
more than 3 km in a north-south direction and has been subdivided into the Trinidad deposit and San Ignacio areas.
The major mineralized structure in the Trinidad
deposit area is composed of a sheeted and stockworked quartz-carbonate vein system referred to as the Stockwork Zone located between
the primary Trinidad and Bonanza structures. In addition, several secondary vein systems are present locally in the hanging wall and
footwall of the Trinidad and Bonanza structures.
The Victoria mineralized zone is located approximately
350 m east of the Trinidad vein and north of the current underground operations of the San Jose Mine. It is structurally related to the
same extensional behavior that dominates the Trinidad deposit with a similar style of mineralization, corresponding to a low sulfidation
epithermal deposit formed in a shallow crustal environment with a relatively low temperature resulting in the precipitation of silver
and gold mineralization.
In the opinion of the QPs, the knowledge of the
Trinidad and Victoria deposits, the settings, lithologies, and structural and alteration controls on mineralization is sufficient to
support the Mineral Resources and Mineral Reserves estimation.
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| 25.3 | Exploration,
drilling and analytical data collection in support of Mineral Resource estimation |
Drill holes drilled under Cuzcatlan management
in the period 2005 to 2023 have data collected using industry-standard practices. Drill orientations are appropriate to the orientation
of the mineralization and core logging meets industry standards for exploration of an epithermal-style deposit.
Geotechnical logging is sufficient to support
Mineral Resource estimation with the data for the Trinidad deposit being used to support detailed mine planning for the underground mine
for the last 12 years of operation.
Collar and downhole surveys have been performed
using industry-standard instrumentation. Any uncertainties in survey information have been incorporated into subsequent resource confidence
category classification.
All collection, splitting, and bagging of channel
and core samples were carried out by Cuzcatlan personnel since 2005 representing 98 % of all information collected at the mine. No material
factors were identified with the drilling programs that could affect Mineral Resource or Mineral Reserve estimation.
Sample preparation and assaying for samples that
support Mineral Resource estimation has followed approximately similar procedures for most drill programs since 2005. The preparation
and assay procedures are adequate for the type of deposit and follow industry standard practices.
Sample security procedures met industry standards
at the time the samples were collected. Current core and pulp sample storage procedures and storage areas are consistent with industry
standards.
Paul Weedon
Mr. Weedon has visited the San Jose Mine
on multiple occasions and during these visits has reviewed the geological interpretations and drill core. He is of the opinion that the
data verification programs performed on the data collected from exploration are adequate to support the geological interpretations, the
analytical and database quality, and Mineral Resource estimation at the San Jose Mine.
Eric Chapman
Mr. Chapman has personally verified data
used in the Mineral Resource estimation, including the database, collars and downhole surveys, geological logs and assays, estimation
parameters, and mine reconciliation.
Mr. Chapman is of the opinion that the geological
and assay data stored in the database is representative of that reported from the laboratories and is suitable for usage in Mineral Resource
estimation.
Monthly and quarterly QC reports detailing results
for exploration drilling, infill drilling and channel sampling are received and reviewed by Mr. Chapman on an ongoing basis. Any
discrepancies identified are immediately followed up with site staff for further investigation.
To further verify the assay data,
Mr. Chapman has randomly selected assay data from the database and compared the assay results stored to that of the original
assay certificates. Mr.
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Chapman is of the opinion that the geological and assay data stored in the database is representative of that reported from
the laboratories and is suitable for usage in Mineral Resource estimation.
Raul Espinoza
Mr. Espinoza has reviewed on site the current
mining methods and verified the Mineral Reserve estimation methodology including review of documents and discussions with relevant Cuzcatlan
personnel regarding permitting, metallurgical testwork and processing, operating and capital expenditure requirements.
Mr. Espinoza is of the opinion that the
parameters used for the estimation of Mineral Reserves based on the proposed mining method, geotechnical studies, operational, processing
and cost estimates are reasonable and representative for the San Jose Mine.
Mathieu Veillette
Mr. Veillette has been providing technical
support with respect to tailings and water management since September 2022. Mr. Veillette has assisted SRK consulting, the
Engineer of Record (EoR), in the management of the tailings facilities and reviewed all technical documents related to tailings and water
management. The San Jose Mine has a water balance with a closed circuit where effluent is not discharged and only water treatment water
from the nearby community is used as required. As of the effective date of this Report, it is the opinion of Mr. Veillette that
the partially closed tailings dam is well managed with about 2 m of freeboard below the spillway invert and the dry stack is also well
managed.
Patricia Gonzalez
Ms. Gonzalez has reviewed the extensive
body of metallurgical investigation comprising several phases of testwork and, in addition, has been personally involved as the plant
superintendent with the extensive history of treating ore at the operation since 2011. In the opinion of the Ms. Gonzalez, the San
Jose Mine metallurgical samples tested, and the ore that is presently treated in the plant is representative of the orebody as a whole
in respect to grade and metallurgical response. Differences between vein systems are minimal with regard to recovery.
Ms. Gonzalez also works closely with the
relevant departments to execute the necessary environmental and community programs as part of Fortuna’s Environmental, Social,
and Governance (ESG) criteria.
| 25.4 | Metallurgical
testwork |
Metallurgical test work included the following
evaluations:
| · | Bond
ball mill work index. |
| · | Rougher
flotation test work with three stages of cleaning. |
| · | Locked
cycle flotation test work. |
| · | Rougher
kinetics flotation. |
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A total of 25 samples have been tested to establish
the metallurgical characteristics of the Victoria mineralized zone. Metallurgical recoveries obtained from samples with silver head grades
ranging from 120 to 160 g/t were 87.74 to 90.11 % for gold and 88.13 to 89.71 % for silver. Based on the results it was concluded that
the Victoria mineralized zone mineralization follows the same metallurgical recovery trend as the current operation experiences. Additionally,
mineralogical studies did not detect mineral types different from what is currently being processed from the Trinidad deposit.
There is no indication that the characteristics
of the material being mined will change, and therefore the recovery assumptions applied for future mining are considered as reasonable
for the LOMP.
Deleterious elements, such as fluorine, base
metals and iron-oxide, detected in ore located in certain parts of the deposit have the potential to affect metallurgical recovery or
economics due to penalties that could be applied during smelting. Mine scheduling and appropriate treatment in the processing facility
are designed to minimize any impact from deleterious elements.
| 25.5 | Mineral
Resource estimation |
Mineral Resource estimation used drill core and
channel samples in conjunction with underground mapping to construct three-dimensional wireframes to define individual vein structures.
Samples were selected inside these wireframes, coded, composited and top cuts applied if applicable. Boundaries were treated as hard
with statistical and geostatistical analysis conducted on composites identified in individual veins. Silver and gold grades were estimated
into a geological block model consisting of 2 m x 2 m x 2 m SMU representing each vein. All veins in the Trinidad deposit and the Victoria
main structure were estimated by OK. Estimated grades were validated globally, locally, visually, and (where possible) through production
reconciliation prior to tabulation of the Mineral Resources.
Resource confidence classification considers
a number of aspects affecting confidence in the resource estimation including; geological continuity and complexity; data density and
orientation; data accuracy and precision; grade continuity; and simulated grade variability.
The QP is of the opinion that the Mineral Resources
have been estimated using standard industry practices, and conform to the requirements of CIM (2014).
It is the opinion of the QP that by the application
of a silver equivalent value taking into consideration the average metallurgical recovery and long term metal prices for each metal,
and the determination of a reasonable cut-off grade using actual operating costs, as well as the exclusion of Mineral Resources identified
as being isolated or economically unviable using a floating stope optimizer, the Mineral Resources have ‘reasonable prospects for
eventual economic extraction’.
Factors that may affect the estimates include:
metal price and exchange rate assumptions; changes to the assumptions used to generate the cut-off grade; changes in local interpretations
of mineralization geometry and continuity of mineralized zones; changes to geological and mineralization shape and geological and grade
continuity assumptions; variations in density and domain assignments; geometallurgical assumptions; changes to geotechnical, mining,
dilution, and metallurgical recovery assumptions; change to the input and design parameter assumptions that pertain to the conceptual
stope designs constraining the estimates; and assumptions as to the continued ability to access the site, retain mineral
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and surface rights titles, maintain environment
and other regulatory permits, and maintain the social license to operate.
| 25.6 | Mineral Reserve estimation |
Mineral Reserves have been converted from Measured
and Indicated Mineral Resources.
The Mineral Reserve estimation procedure for
the Trinidad deposit is defined as follows:
| · | Review
of Mineral Resources in longitudinal sections and grade–tonnage curves. |
| · | Identification
and removal of inaccessible Mineral Resources based on current mining practices - such as
crown pillars and isolated areas. |
| · | Dilution
of tonnes and grades based on dilution levels encountered during the previous 12 months of
production preceding Mineral Reserve estimation. |
| · | After
obtaining the resources with diluted tonnages and grades, the value per tonne of each SMU
is determined based on metal prices and metallurgical recoveries for each metal. |
| · | A
breakeven cut-off grade is determined based on operational costs of production, processing,
general expenses and administrative, and distribution costs (total operating cost in US$/t)
and converted into a silver equivalent grade. If the silver equivalent grade of an SMU is
higher than the breakeven cut-off grade, the SMU is considered as part of the Mineral Reserve
otherwise the SMU is regarded as part of the Mineral Resource. This evaluation is conducted
in MSO. |
| · | Evaluate
location and dimensions of potential pillars based on the proposed mining methodology. |
| · | Removal
of inaccessible areas and material identified as pillars or crown pillars to account for
mining recovery based on current mining practices and mine architecture. |
| · | Depletion
of Mineral Reserves relating to operational extraction between July 1 and December 31,
2023. |
| · | Reconciliation
of the reserve block model against mine production between July 1 and December 31,
2023, to confirm estimation parameters. |
| · | Mineral
Reserve tabulation and reporting as of December 31, 2023. |
Mineral Reserves will support just a one-year
LOMP considering 350 days in the year for production and a capacity rate of 2,100 tpd. The expectation based on an optimized production
schedule is for an annual average production of approximately 3.2 Moz of silver and 20 koz of gold. The remaining mine life is from the
year 2024.
The conversion of Mineral Resources to Mineral
Reserves was undertaken using industry recognized methods, actual operational costs, capital costs, and plant performance data. Thus,
it is considered to be representative of future operational conditions. This Report has been prepared with the latest information regarding
environmental and closure cost requirements.
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The QP is of the opinion that the Proven and
Probable Mineral Reserves estimate has been undertaken with reasonable care and has been classified using the 2014 CIM Definition Standards.
Factors that may affect the estimates include:
metal price and exchange rate assumptions; changes to the assumptions used to generate the cut-off grade; changes in local interpretations
of mineralization geometry and continuity of mineralized zones; changes to geological and mineralization shape and geological and grade
continuity assumptions; variations in density and domain assignments; geometallurgical assumptions; changes to geotechnical, mining,
dilution, and metallurgical recovery assumptions; change to the input and design parameter assumptions that pertain to the conceptual
stope designs constraining the estimates; and assumptions as to the continued ability to access the site, retain mineral and surface
rights titles, maintain environment and other regulatory permits, and maintain the social license to operate.
Mining at San Jose is conducted by contractors
based on conventional OCF and SLS, using a mechanized extraction methodology.
Since September 2011 Cuzcatlan has successfully
managed the underground operation of the San Jose Mine, processing over 10.36 Mt of ore and producing 66.8 Moz of silver and 457.8 koz
of gold as of December 31, 2023.
The QP is of the opinion that:
| · | The
mining methods OCF and SLS being used are appropriate for the deposit being mined. The underground
mine design, stockpiles, tailings facilities, and equipment fleet selection are appropriate
for the operation. |
| · | The
mine plan is based on historical mining and planning methods practiced at the operation for
the previous seven years and presents low risk. |
| · | The
mobile equipment fleet presented is based on the actual present-day mining operations, which
are known to achieve the production targets set out in the LOMP. |
| · | All
mine infrastructure and supporting facilities meet the needs of the current mine plan and
production rate. |
The current process plant design is split into
four principal stages including: crushing; milling; flotation; and thickening; filtering and shipping.
The QP considers the process requirements to
be well understood, and consistent based on the actual observed conditions in the operating plant.
The QP considers that all mine and process infrastructure
and supporting facilities are included in the present general layout to ensure that they meet the needs of the mine plan and production
rate and notes that:
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| · | The
San Jose Mine is located 47 km, or one hour by road from the city of Oaxaca, the main service
center for the operation, with good year-round access. |
| · | The
mine site infrastructure has a compact layout footprint of 50.15 ha, with an additional 69.69
ha for the tailings storage facilities. |
| · | The
dry stack tailings construction of the final stage was completed in 2021 increasing total
capacity to 4,033,000 m3. |
| · | Power
is provided to the mine from the main grid via a 115,000-volt circuit, as well as a secondary
reserve power supply line, all managed by CFE. |
| · | Water
requirements are 2.7 m3 to process one tonne of ore being primarily sourced from
recirculation activities, and where top up is required, from the tailings storage facility. |
| · | All
process buildings and offices for operating the mine have been constructed, with camp facilities
not required due to the proximity of the site to urban centers. |
| 25.10 | Markets
and contracts |
Since the operation commenced commercial
production in September 2011, a corporate decision was made to sell the concentrate on the open market. In order to get the best
commercial terms for the concentrates, it is Fortuna’s policy to sign contracts for periods no longer than one year. All commercial
terms entered between the buyer and Cuzcatlan are regarded confidential but are considered to be within standard industry norms.
The QP has reviewed the information provided
by Fortuna on marketing, contracts, metal price projections and exchange rate forecasts and notes that the information provided support
the assumptions used in this Report and are consistent with the source documents, and that the information is consistent with what is
publicly available within industry norms.
| 25.11 | Environmental,
permitting and social considerations |
The mining operation has been developed
in strict compliance with the regulations and permits required by the government agencies involved in the mining sector. In addition,
all work follows the international quality and safety standards set forth under standards ISO 14001 and OHSAS 18000.
To the extent known, all permits that
are required by Mexican law for the mining operation have been obtained. The tailings facility has sufficient storage capacity to support
the LOMP.
Cuzcatlan continues with developing sustainable
annual programs for the benefit of local communities, including educational, nutritional and economic programs. There is a good relationship
between the company and local communities. This will aid the development and continuity of the mining operation and improve the standard
of living and economies of local communities.
The mine plan anticipates closure of
the operation at the end of 2024. The Company has assigned a dedicated team to review and update a multiyear progressive mine closure
and monitoring plan with a current estimated budget of US$ 27 million, which will begin its implementation during 2024.
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25.12 | Capital and operating costs |
Capital and operating cost estimates
are based on established cost experience gained from current operations, projected budget data and quotes from manufacturers and suppliers.
Sustaining capital cost has been considered
as part of the operating costs and covered by the projected cash flow generation in 2024.
Operating
cost includes site costs and operating expenses to maintain the operation. These operating costs are analyzed on a functional
basis and the cost structure can differ from the operating costs reported by the financial statements published by Fortuna.
Costs were not allocated to the operation
for Brownfields exploration, with this activity being assigned to Fortuna as an opportunity cost to extend the LOMP beyond 2024.
The QP considers that costs estimated
for the San Jose Mine as reasonable based on industry-standard practices and actual costs observed for 2023 and production projected
for 2024.
Fortuna is using the provision for producing
issuers, whereby producing issuers may exclude the information required under Item 22 for technical reports on properties currently in
production and where no material production expansion is planned.
The global after-tax financial results
exhibit a negative outcome when factoring in exploration costs and the total mine closure cost. However, the projected financial outcome
for 2024, considering only operational costs, shows a positive result. Fortuna expresses its commitment to covering Brownfields exploration
costs for 2024 and the subsequent expenses upon cessation of mining operations using funds derived from corporate profits. Given this,
the QP believes it is reasonable to continue mining operations throughout the planned operational period in 2024 to alleviate the negative
financial and social results of mine closure and support the current Mineral Reserve declaration.
| 25.14 | Risks and opportunities |
A number of opportunities and risks were
identified by the QPs during the evaluation of the San Jose Mine.
Opportunities include:
| · | Improvements
in mining productivity through optimizing the mining cycle. As shotcreting comprises a significant
component of the mining cycle, tests are being done to reduce the curing time from three
to two hours which would improve the mining cycle. |
| · | Completing
the raise bore initiatives currently underway in the central and northern zones of the Trinidad
deposit. This will ensure 100 % air coverage throughout the remainder of the mine life. |
| · | Definition
of Mineral Reserves associated with higher-grade mineralization identified in the Victoria
mineralized structure. |
| · | Exploration
potential exists for the Yessi vein, a new blind zone of alteration and brecciation that
has been interpreted as striking northwest to southeast and |
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| | intersecting the Victoria mineralized
zone, where drilling has intercepted some high-grade gold and silver mineralization. |
Risks include:
| · | On
January 2, 2023, SEMARNAT served Cuzcatlan a resolution confirming the nullity of the
previously granted 12-year EIA extension. Cuzcatlan challenged the annulment of the EIA via
a nullity trial presented before the Federal Administrative Court in Mexico City on January 10,
2023. On October 30, 2023, the Mexican Federal Administrative Court ruled in favor of
Cuzcatlan and re-instated the 12-year EIA. The decision of the Mexican Federal Administrative
Court has been appealed and was admitted by the Collegiate Court in January 2024. Cuzcatlan
filed a response with the Collegiate Court in February 2024. A decision of the Collegiate
Court is expected within the next six to 12 months. The permanent injunction that Cuzcatlan
already has remains in effect. |
| · | Metallurgical
recovery could be lower than estimated in ore that is estimated to have an elevated iron
oxide content, which represents approximately 30 % of the plant feed in the LOMP. |
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The information set forth in this Report continues
to demonstrate that the San Jose Mine is a technically and economically viable operation.
Recommendations
for the next phase of work have been broken into those related to ongoing exploration activities and those related to additional technical
studies focused on operational improvements. Recommended work programs are independent of each other and can be conducted concurrently
unless otherwise stated. The exploration-related programs are estimated at a total cost of US$ 4.3 million. The operational improvement
studies are recommended to be conducted in-house and therefore do not involve a direct cost.
It is recommended that Cuzcatlan continue
to explore the Trinidad central sector and exploration of the behavior of the Trinidad system at depth to investigate the potential for
mineralization being hosted by the Mesoproterozoic basement. The program would involve the core drilling of 3,300 m at an estimated cost
of US$ 450,000.
| 26.2.2 | Victoria mineralized zone |
It is recommended that Cuzcatlan continue
to explore the Yessi vein discovered in August 2023 to better define the geometry of the structures and establish the continuity
in mineralization. Recommended drilling includes 4,000 m of core at an estimated cost of US$ 690,000.
An extensive and systematic field exploration
program has been carried out since 2020 including a drone magnetometric assessment, structural analysis, fluid inclusion studies and
detailed field work activities resulting in the definition of a first stage drilling program proposal including 4,600 m in 17 core holes
in six structures with geological potential, including the San Juan, San Juan 2, Pastal, San Francisco, Consuelos and San Nicolas; at
an estimated cost of US$1,500,000. The execution of this exploration program is dependent on obtaining the necessary permits from the
government and may not be executed if such permits are denied.
This vein was first explored in 2017
with 3 holes, defining the presence of a dilational region in the convergence of the Maria vein and the footwall of the Trinidad vein.
It is recommended that Cuzcatlan continue to explore the possible kinematic indicators related to extension in the footwall of the Trinidad
trend south of the current operations with the drilling of 1,500 m of core at an estimated cost of US$290,000.
The Guila prospect located on the Reduccion
Tlacolula 2 concession has been identified as an area that has high potential for the discovery of epithermal veins based on detailed
surface mapping. It is recommended that permits be obtained to allow targets to be drilled
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on this concession. If permits are obtained
a drill program consisting of 9,000 m of core holes at an estimated cost of US$ 1,400,000 is recommended.
| 26.3 | Technical
and Operational |
The following technical studies are recommended
to improve the understanding of the San Jose Mine Mineral Reserves and Mineral Resources. With the exception of the delineation drilling,
the studies recommended to be conducted in-house and therefore do not involve a direct cost.
| 26.3.1 | Mineral Resources and Reserves |
| · | Delineation
(infill) drilling. It is recommended that Cuzcatlan continue the delineation drilling
from underground of the Trinidad deposit and Victoria mineralized zone. A total of 20,600
m of core drilling is recommended at a budgeted cost of US$ 2,500,000. |
| · | Assess
the mining potential of the Victoria mineralized zone. A detailed evaluation is recommended
to determine the economic viability of accessing and mining the higher-grade zones of the
Victoria mineralized structure. This will be completed utilizing the operations resources
and part of normal operating cost. |
| · | Bulk
density measurements. It is recommended that the number of bulk density measurements
be increased in secondary veins. If sufficient measurements are obtained, bulk density can
be estimated rather than the presently used density assignment methodology. |
| 26.3.2 | Mining and Processing |
The following are studies recommended
to improve operational decision making and mining costs.
| · | Mining
method. As
part of continuous improvement initiatives to reduce mining cost and to increase mine productivity,
it is recommended to continue with the mining evaluation and geomechanical conditions for
each stope, considering the possibility of increasing the mining height using SLS from 20
to 25 m where possible. |
| · | Mining
dilution. It is advisable for the mine to continue enhancing its blasting practices to
minimize excessive host rock over breaking, which can lead to increased unplanned dilution. |
| · | Optimization
of plant based on metallurgical testwork results for mineralization located in the upper
levels of the mine. The operation has identified a decrease in metallurgical recovery
by approximately 5 % associated with mineralization from the upper levels of the mine, which
recent mineralogical analysis indicates is related to the presence of hematite (iron-oxide).
Additional metallurgical testwork has been initiated with results expected by the end of
March 2024. Based on these results, it is recommended that the processing methodology
is optimized to maximize metallurgical recovery by processing this mineralized material in
batches. The budgeted cost of these tests is US$ 10,000. |
December 31, 2023 | Page 200 of 208 |
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Albinson,
T., 2018. Fluid Inclusion and Petrographic Study of veins in the San Jose del Progreso District, Oaxaca, Mexico for Compañía
Minera Cuzcatlán S.A. de C.V., October 2018.
Alvarez,
L.R., 2009. Historia operativa de la Mina San José y de la Planta Concentradora de San Jerónimo Taviche durante
la operación de Minerales de Oaxaca previa a l compra por parte de Compañía Minera Cuzcatlán: Internal report
for Compañía Minera Cuzcatlán S.A. de C.V., 14p.
Bieniawski,
Z.T., 1989. Engineering Rock Mass Classification. New York: John Wiley, pp 51
Brandt
Engineering & Microanalysis, 2022. Reporte petrográfico descriptivo para la Compañía Minera.
Cuzcatlan. January 29, 2022.
Cardona
Benavides y Asociados SC, 2022. Actualización de Estudio de Hidrología superficial e Hidrogeología para
la Compañía Minera. Cuzcatlan, Informe Técnico, 355 p., July 15, 2022.
Carranza
Alvarado, M., Gómez Caballero, J. A., y Pérez León, C., ed., 1996. Monografía geológico-minera
del Estado de Oaxaca: Consejo de Recursos Minerales, Secretaria de Comercio y Fomento Industrial, Coordinación General de Minería,
Publicación M-17e, 298 p.
Chapman,
E.N., and Kelly, T., 2013a. Technical Report: San Jose Property, Oaxaca, Mexico. Prepared for Fortuna Silver Mines Inc., March 22,
2013.
Chapman,
E.N., and Kelly, T., 2013b. Technical Report: San Jose Property, Oaxaca, Mexico. Prepared for Fortuna Silver Mines Inc., November 22,
2013.
Chapman,
E.N., and Gutierrez, E., 2017. Amended Technical Report: San Jose Property, Oaxaca, Mexico. Prepared for Fortuna Silver Mines
Inc., August 20, 2016.
Chapman,
E.N., and Sinuhaji, A., 2019. Technical Report: San Jose Mine, Oaxaca, Mexico. Prepared for Fortuna Silver Mines Inc., February 22,
2019.
Chlumsky,
Armbrust, and Meyer, 2010. NI 43-101 Technical Report: San Jose Silver Project, Oaxaca, Mexico. Prepared for Fortuna Silver
Mines Inc., June 9, 2010.
CIM,
2014. CIM Definition Standards on Mineral Resources and Mineral Reserves. Prepared by the CIM Standing Committee on Reserve
Definitions. Adopted by the CIM Council, May 10, 2014.
CIM,
2019. CIM Estimation of Mineral Resources and Mineral Reserves Best Practice Guidelines. Adopted by the CIM Council on November 29,
2019.
Consejo
de Recursos Minerales, 1982. Informe geológico preliminar del prospecto minero San Ignacio, municipio de Ejutla de
Crespo Oaxaca, Distrito Minero de Taviche.
Consejo
de Recursos Minerales, 1996. Monografía Geológico-Minera del Estado de Oaxaca, Secretaría de Comercio
y Fomento Industrial, Coordinación General de Minería, pp 37, 58.
Corbett,
G., 2002. Epithermal Gold for Explorationists. AIG Journal-Applied geoscientific practice and research in Australia,
26p.
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Corbett,
G., 2006. Controls to Low Sulfidation Epithermal Au-Ag. Presentation by G. Corbett, 92p.
Dickinson,
W.R., and Lawton, T.F., 2001. Carboniferous to Cretaceous assembly and fragmentation of Mexico. Geological Society of America
Bulletin, v. 113, p. 1142-1160.
Fortuna,
2011. Press Release Titled “Fortuna Begins Commercial Production at San Jose Mine, Mexico”. Vancouver,
Canada, September 1, 2011.
Fortuna,
2023. Press Release Titled “Fortuna updates Mineral Reserves and Mineral Resources”. Vancouver, Canada,
March 21, 2023.
García,
E. 2004. Carta de climas Jalisco. Climatología de la República Mexicana. Proyecto CONABIO-Estadigrafía.
México, DF. 90 p
Hester,
M.G., and Ray, G.E., 2007. Geology, epithermal silver-gold mineralization and mineral resource estimate at the San Jose Mine
property, Oaxaca, Mexico: NI43-101 Technical Report prepared for Fortuna Silver Mines Inc., 58p.
Journel,
A.G., 1974. Geostatistics for conditional simulation of ore bodies. Econ. Geol., V.69, pp673-687.
Lechner,
M.J., and Earnest, D.F., 2009. Mineral Resource Estimate, Trinidad Deposit, San Jose Project, Oaxaca, Mexico. Prepared for
Fortuna Silver Mines Inc., December 10, 2009.
Marinos
P., Marinos V., Hoek, E., 2007. The Geological Strength Index (GSI): A Characterization tool for Assessing Engineering Properties
for Rock Masses in Proceedings of the International Workshop on Rock Mass Classification in Underground Mining., pp87–94.
Martinez-Serrano,
R.G., Solis-Pichardo, G., Flores-Marquez, E.L., Macias-Romo, C, Delgado-Duran, J., 2008. Geochemical and Sr-Nd isotropic characterization
of the Miocene volcanic events in the Sierra Madre del Sur, central and southeastern Oaxaca, Mexico. Revista Mexicana de Ciencias
Geologicas v.25, no.1, pp1-20.
Mora.
C., J. Valley W., Ortega- Gutiérrez F., 1986. The temperature and Pressure Conditions of Grenvilleage granulite facies
metamorphism of the Oaxacan Complex. Southern Mexico. Rev. Inst. Geología, UNAM, V. 6, No. 2, p. 222-242.
Ortega-Gutierrez
F., 1988. North American Ocean Continent Transect Corridor H 3 from the Acapulco Trench to the Gulf of Mexico across Southern
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Ortega-Gutiérrez,
F., Mitre-Salazar, L. M., Roldán-Quintana, J., Aranda-Gómez, J. J., Morán-Zenteno, D. J., Alaniz-Álvarez,
S. A., Nieto-Samaniego, Á. F., 1992. Carta geológica de la República Mexicana, quinta edición
escala 1:2.000,000: México, D. F., Universidad Nacional Autónoma de México, Instituto de Geología; Secretaría
de Energía, Minas e Industria Paraestatal, Consejo de Recursos Minerales, 1 mapa.
Osterman,
C., 2004. Geology and silver-gold mineralization at the San Jose Mine and the Taviche Mining District, Oaxaca, Mexico. A NI
43-101 Technical Report prepared for Continuum Resources.
Ravenscroft,
P.J., 1992. Recoverable reserve estimation by conditional simulation, in Case Histories and Methods in Mineral Resource
Estimation, Geological Special Publication, No.63. (Ed. Annels, A.E.) pp.289-298.
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Ray, G.E., 2006. Geology and epithermal
silver-gold mineralization at the San Jose and Taviche properties, Oaxaca, Mexico: A NI 43-101 Technical Report prepared for Fortuna
Silver Mines Inc.
Sánchez
Rojas, L. E., Castro Rodríguez, M.G., Ney Aranda Osorio, J., Zarate Lopez, J., Zarate Barradas, R., y Salinas Rodríguez,
J.M., 2003. Carta geológico-minera Zaachila E14-12, Escala 1:250,000, 81p.
Sinclair,
A.J. and Blackwell, G.H., 2002. Applied Mineral Inventory Estimation. (1st Edition) Cambridge University Press,
381pp.
SVS,
2015. Conceptual study of the extension to 3000 tpd of San Jose Mine, Oaxaca, Mexico, March 2015.
William,
A., Hustrulid, W. A., Hustrulid, R. C., 2001. SME Underground Mining methods, Mining Dilution in moderate-to-narrow width
deposits. pp 615.
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Certificates
CERTIFICATE of QUALIFIED PERSON
(a) I, Eric Chapman, Senior Vice
President of Technical Services for Fortuna Silver Mines Inc., 650-200 Burrard St, Vancouver, BC, V6C 3L6 Canada; do hereby certify that:
(b) I am the co-author of the technical
report titled “Fortuna Silver Mines Inc. San Jose Mine, Oaxaca, Mexico” that has an effective date of December 31, 2023
(the “Technical Report”).
(c) I graduated with a Bachelor
of Science (Honors) Degree in Geology from the University of Southampton (UK) in 1996 and a Master of Science (Distinction) Degree in
Mining Geology from the Camborne School of Mines (UK) in 2003. I am a Professional Geologist of the Engineers and Geoscientists of the
Province of British Columbia (Registration No. 36328) and a Chartered Geologist of the Geological Society of London (Membership
No. 1007330). I have been practicing as a geoscientist and preparing resource estimates for approximately twenty years and have
completed more than thirty resource estimates for a variety of deposit types such as epithermal gold/silver veins, porphyry gold deposits,
and volcanogenic massive sulfide deposits. I have completed at least fifteen Mineral Resource estimates for precious metal projects over
the past five years.
As a result of my experience and qualifications, I
am a Qualified Person as defined in National Instrument 43–101 Standards of Disclosure for Mineral Projects (“NI 43–101”).
(d) I last visited the mine on November 14th
to 15th, 2023.
(e) I am responsible for the preparation
of Sections 1.1 to 1.4, Sections 1.6 and 1.7, Section 1.9, Section 1.19, Sections 2 to 7, Section 11, Sections 12.1 to
12.4, Section 12.7, Sections 12.9 to 12.11, Section 14, Sections 25.1 to 25.3, Section 25.5, Section 25.14, Section 26.1,
Section 26.3, and Section 27.
(f) I
am not independent of Fortuna Silver Mines Inc (“Fortuna”) as independence is described by Section 1.5 of NI
43–101. I am a Fortuna employee.
(g) I have been an employee of Fortuna
and involved with the property that is the subject of the Technical Report since May 2011.
(h) I
have read NI 43–101 and Form 43-101F1, and the sections of the Technical Report for which I am responsible have been prepared
in compliance with that Instrument and Form.
(i) As
of the effective date of the Technical Report, to the best of my knowledge, information and belief, the sections of the Technical Report
for which I am responsible contain all scientific and technical information that is required to be disclosed to make the Technical Report
not misleading.
Dated at Vancouver, BC, Canada, March 8, 2024.
[signed]
Eric Chapman, P. Geo.
December 31, 2023 | Page 204 of 208 |
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CERTIFICATE of QUALIFIED PERSON
(a) I, Paul Weedon, Senior Vice
President, Exploration of Fortuna Silver Mines Inc. (“Fortuna”), 200 Burrard Street, Suite 650, Vancouver, BC V6C 3L6,
Canada, do hereby certify that:
(b) I am the co-author of the technical
report titled “Fortuna Silver Mines Inc. San Jose Mine, Oaxaca, Mexico” that has an effective date of December 31, 2023
(the “Technical Report”).
(c) I
graduated from Curtin University, Western Australia in December 1991 with a Bachelor of Science (Geology), and a Post Graduate Diploma
of Economic Geology (Distinction) and have practiced my profession continuously since 1991. I am a professional
Geologist and a Member of the Australian Institute of Geoscientists (MAIG #6001). I have worked across all roles of exploration and mining
geology, covering open-pit and underground gold mining in production
roles up to Technical Services Manager for large scale complex operations. My exploration experience extends from project generation
through to project development and corporate roles. These roles have been conducted across Australasia, Africa and Latin America. I have
held my current position of Senior Vice President – Exploration for Fortuna Silver Mines Inc since October 2021.
As a result of my experience and qualifications, I
am a Qualified Person as defined in National Instrument 43–101 Standards of Disclosure for Mineral Projects (“NI 43–101”).
(d) I last visited the mine from
August 11th to 13th, 2023.
(e) I am responsible for the preparation
of Section 1.5, Section 1.20.1, Sections 8 to 10, Section 12.11, Section 25.3.1, Section 26.2, and Section 27.
(f) I
am not independent of Fortuna Silver Mines Inc (“Fortuna”) as independence is described by Section 1.5 of NI
43–101. I am a Fortuna employee.
(g) I have been an employee of Fortuna
and involved with the property that is the subject of the Technical Report since August 2021.
(h) I
have read NI 43–101 and Form 43-101F1, and the sections of the Technical Report for which I am responsible have been prepared
in compliance with that Instrument and Form.
(i) As
of the effective date of the Technical Report, to the best of my knowledge, information and belief, the sections of the Technical Report
for which I am responsible contain all scientific and technical information that is required to be disclosed to make the Technical Report
not misleading.
Dated at Perth, WA, Australia, March
8, 2024.
[signed]
Paul Weedon, MAIG.
December 31, 2023 | Page 205 of 208 |
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CERTIFICATE of QUALIFIED PERSON
(a) I, Raul Espinoza, Technical
Services Director of Fortuna Silver Mines Inc., 650-200 Burrard St, Vancouver, BC, V6C 3L6 Canada; do hereby certify that:
(b) I am the co-author of the technical
report titled “Fortuna Silver Mines Inc. San Jose Mine, Oaxaca, Mexico” that has an effective date of December 31, 2023
(the “Technical Report”).
(c) I graduated with a Bachelor
of Science Degree in Mining Engineering from Pontificia Universidad Catolica del Peru in 2001 and a Master of Engineering Science in
Mining from Curtin University, Australia, in 2014. I am a Fellow member of the Australasian Institute of Mining and Metallurgy and registered
as a Chartered Professional in Mining - FAusIMM (CP) with Membership No. 309581. I have practiced my profession for 22 years and
been preparing reserve estimates for approximately 11 years. My experience has covered operational, technical, managerial and consultancy
functions for open pit and underground mines, from early-stage projects through to producing mines in Argentina, Peru, Australia, Canada
and Mexico.
As a result of my experience and qualifications, I
am a Qualified Person as defined in National Instrument 43–101 Standards of Disclosure for Mineral Projects (“NI 43–101”).
(d) I last visited the mine on December 4th
and 6th, 2023.
(e) I am responsible for the preparation
of Section 1.7, Sections 1.10 and 1.11, Sections 1.13 and 1.14, Sections 1.16 to 1.20, Section 12.8, Section 12.11, Section 15,
Section 16.1, Sections 16.3 to 16.8, Sections 18.1 and 18.2, Sections 18.5 to 18.9, Section 19, Sections 21 to 24, Section 25.3.1,
Sections 25.6 and 25.7, Sections 25.9 and 25.10, Sections 25.12 to 25.14, Section 26.3, and Section 27.
(f) I am not independent of Fortuna
Silver Mines Inc (“Fortuna”) as independence is described by Section 1.5 of NI 43–101. I am a Fortuna employee.
(g) I have been an employee of Fortuna
and involved with the property that is the subject of the Technical Report since June2022.
(h) I have read NI 43–101
and Form 43-101F1, and the sections of the Technical Report for which I am responsible have been prepared in compliance with that
Instrument and Form.
(i) As of the effective date of
the Technical Report, to the best of my knowledge, information and belief, the sections of the Technical Report for which I am responsible
contain all scientific and technical information that is required to be disclosed to make the Technical Report not misleading.
Dated at Vancouver, BC, Canada, March 8, 2024.
[signed]
Raul Espinoza, FAusIMM (CP)
December 31, 2023 | Page 206 of 208 |
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CERTIFICATE of QUALIFIED PERSON
(a) I, Mathieu F. Veillette,
Director, Geotechnical, Tailings and Water for Fortuna Silver Mines Inc., 650-200 Burrard St, Vancouver, BC, V6C 3L6 Canada; do
hereby certify that:
(b) I am the co-author of the technical
report titled “Fortuna Silver Mines Inc. San Jose Mine, Oaxaca, Mexico” that has an effective date of December 31, 2023
(the “Technical Report”).
(c) I graduated with a Bachelor
of Science Degree in Civil Engineering in 1997 from Queen’s University and a Graduate Diploma Business Administration from Simon
Fraser University in 2018. I am a Professional Engineer of the Association of Professional Engineers and Geoscientists of the Province
of British Columbia (Registration No. 28397), also a Professional Engineer from Colorado (Registration No. 36639) and Alaska
(Registration No. 10914). I have practiced my profession continuously for 25 years in geotechnical and water management related
fields. The majority of my experience has been in the mining industry including international projects on all stages of the mining process
from advanced exploration through decommissioning and reclamation. My relevant work experience includes analysis, site investigations,
design, construction, dewatering and operation of open pits, waste dumps, heap leach pads, tailings storage facilities, process ponds,
water dams, diversion structures and other mining facilities in Canada (BC, QC), USA (CO, UT, NM, AZ, MT, AK, SC), México, Panamá,
Venezuela, Guyana, Peru, Chile, Argentina, Bolivia, Australia, New Zealand and New Caledonia.
As a result of my experience and qualifications, I
am a Qualified Person as defined in National Instrument 43–101 Standards of Disclosure for Mineral Projects (“NI 43–101”).
(d) I last visited the mine from
October 31st to November 2nd, 2023.
(e) I am responsible for the
preparation of Section 2.3, Sections 12.5 and 12.11, Section 16.2, Sections 18.3 and 18.4, Sections 20.3.3, and 20.3.4,
Section 25.3.1, and Section 27.
(f) I am not independent of Fortuna
Silver Mines Inc (“Fortuna”) as independence is described by Section 1.5 of NI 43–101. I am a Fortuna employee.
(g) I have been an employee of Fortuna
since August 2022 and involved with the property that is the subject of the Technical Report since September 2022.
(h) I have read NI 43–101
and Form 43-101F1, and the sections of the Technical Report for which I am responsible have been prepared in compliance with that
Instrument and Form.
(i) As of the effective date of
the Technical Report, to the best of my knowledge, information and belief, the sections of the Technical Report for which I am responsible
contain all scientific and technical information that is required to be disclosed to make the Technical Report not misleading.
Dated at Vancouver, BC, Canada,
March 8, 2024.
[signed]
Mathieu F. Veillette, P.Eng.
December 31, 2023 | Page 207 of 208 |
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CERTIFICATE of QUALIFIED PERSON
(a) I, Patricia Gonzalez, Director
of Operations for Minera Cuzcatlan, Carretera Oaxaca-Huatulco km 48 San Jose del Progreso, Oaxaca CP 71550, Oaxaca - Mexico; do hereby
certify that:
(b) I am the co-author of the technical
report titled “Fortuna Silver Mines Inc. San Jose Mine, Oaxaca, Mexico” that has an effective date of December 31, 2023
(the “Technical Report”).
(c) I graduated with a Bachelor
of Science Degree in Chemical Engineering from Universidad Autónoma de Nuevo León, México in 2000 and a Master of
Business Administration from Instituto Tecnologico y de Estudios Superiores de Monterrey, México in 2023. I have practiced my
profession for 23 years and covered research and metallurgical technical functions for 11 years for various mines and metals such as
silver, gold, lead, zinc, and copper. My experience has covered operational, technical managerial and consultancy functions in mines
in México. I am a qualified professional member registered in Mining and Metallurgical Society of America #1586QP.
As a result of my experience and qualifications, I
am a Qualified Person as defined in National Instrument 43–101 Standards of Disclosure for Mineral Projects (“NI 43–101”).
(d) I am employed at the mining
operation and therefore visit the mine every weekday throughout the year.
(e) I am responsible for the preparation
of Section 1.8, Section 1.12, Section 1.15, Section 12.6, Section 12.11, Section 13, Section 15, Section 17,
Sections 20.1 and 20.2, Sections 20.3.1 and 20.3.2, Sections 20.3.5 to 20.3.11, Sections 20.4 to 20.7, Section 25.3.1, Section 25.4,
Section 25.8, Section 25.11, Section 25.14, and Section 27.
(f) I am not independent of Fortuna
Silver Mines Inc (“Fortuna”) as independence is described by Section 1.5 of NI 43–101. I am a Minera Cuzcatlan
employee.
(g) I have been an employee of Minera
Cuzcatlan since April 2011 and involved with the property that is the subject of the Technical Report since that date.
(h) I have read NI 43–101
and Form 43-101F1, and the sections of the Technical Report for which I am responsible have been prepared in compliance with that
Instrument and Form.
(i) As of the effective date of
the Technical Report, to the best of my knowledge, information and belief, the sections of the Technical Report for which I am responsible
contain all scientific and technical information that is required to be disclosed to make the Technical Report not misleading.
Dated at Oaxaca, Mexico, March 8, 2024.
[signed]
Patricia
Gonzalez, MMSA QP
December 31, 2023 | Page 208 of 208 |
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Exhibit 99.2
CONSENT OF AUTHOR
March 8, 2024
VIA SEDAR+
British Columbia Securities Commission
Alberta Securities
Commission
Financial and Consumer Affairs Authority of Saskatchewan
The Manitoba Securities Commission
Ontario Securities Commission
Nova Scotia Securities
Commission
Securities, Financial and Consumer Services Commission
(New Brunswick)
Office of the Superintendent of Securities (Prince Edward Island)
Office of the Superintendent of Securities, Service
Newfoundland and Labrador
Autorité des marchés financiers
Re: | Technical Report (the “Report”)
entitled “Fortuna Silver Mines Inc: San Jose Mine, Oaxaca, Mexico” with
an effective date of December 31, 2023, prepared for Fortuna Silver Mines Inc. (the “Company”) |
I, the undersigned, a Qualified Person as defined in National
Instrument 43-101 – Standards of Disclosure for Mineral Projects, hereby consent to the public filing of the Report by the
Company.
“Eric Chapman” | |
Eric Chapman, P. Geo | |
Exhibit 99.3
CONSENT OF AUTHOR
March 8, 2024
VIA SEDAR+
British Columbia Securities Commission
Alberta Securities
Commission
Financial and Consumer Affairs Authority of Saskatchewan
The Manitoba Securities Commission
Ontario Securities Commission
Nova Scotia Securities
Commission
Securities, Financial and Consumer Services Commission
(New Brunswick)
Office of the Superintendent of Securities (Prince Edward Island)
Office of the Superintendent of Securities, Service
Newfoundland and Labrador
Autorité des marchés financiers
Re: | Technical Report (the “Report”)
entitled “Fortuna Silver Mines Inc: San Jose Mine, Oaxaca, Mexico” with
an effective date of December 31, 2023, prepared for Fortuna Silver Mines Inc. (the “Company”) |
I, the undersigned, a Qualified Person as defined in National
Instrument 43-101 – Standards of Disclosure for Mineral Projects, hereby consent to the public filing of the Report by the
Company.
“Paul Weedon” | |
Paul Weedon, MAIG | |
Exhibit 99.4
CONSENT OF AUTHOR
March 8, 2024
VIA SEDAR+
British Columbia Securities Commission
Alberta Securities
Commission
Financial and Consumer Affairs Authority of Saskatchewan
The Manitoba Securities Commission
Ontario Securities Commission
Nova Scotia Securities
Commission
Securities, Financial and Consumer Services Commission
(New Brunswick)
Office of the Superintendent of Securities (Prince Edward Island)
Office of the Superintendent of Securities, Service
Newfoundland and Labrador
Autorité des marchés financiers
Re: | Technical Report (the “Report”)
entitled “Fortuna Silver Mines Inc: San Jose Mine, Oaxaca, Mexico” with
an effective date of December 31, 2023, prepared for Fortuna Silver Mines Inc. (the “Company”) |
I, the undersigned, a Qualified Person as defined in National
Instrument 43-101 – Standards of Disclosure for Mineral Projects, hereby consent to the public filing of the Report by the
Company.
“Raul Espinoza” | |
Raul Espinoza, FAusIMM (CP) | |
Exhibit 99.5
CONSENT OF AUTHOR
March 8, 2024
VIA SEDAR+
British Columbia Securities Commission
Alberta Securities
Commission
Financial and Consumer Affairs Authority of Saskatchewan
The Manitoba Securities Commission
Ontario Securities Commission
Nova Scotia Securities
Commission
Securities, Financial and Consumer Services Commission
(New Brunswick)
Office of the Superintendent of Securities (Prince Edward Island)
Office of the Superintendent of Securities, Service
Newfoundland and Labrador
Autorité des marchés financiers
Re: | Technical Report (the “Report”)
entitled “Fortuna Silver Mines Inc: San Jose Mine, Oaxaca, Mexico” with
an effective date of December 31, 2023, prepared for Fortuna Silver Mines Inc. (the “Company”) |
I, the undersigned, a Qualified Person as defined in National
Instrument 43-101 – Standards of Disclosure for Mineral Projects, hereby consent to the public filing of the Report by the
Company.
“Mathieu Veillette” | |
Mathieu Veillette, P.Eng. | |
Exhibit 99.6
CONSENT OF AUTHOR
March 8, 2024
VIA SEDAR+
British Columbia Securities
Commission
Alberta Securities Commission
Financial and Consumer
Affairs Authority of Saskatchewan
The Manitoba Securities
Commission
Ontario Securities Commission
Nova Scotia Securities
Commission
Securities, Financial
and Consumer Services Commission (New Brunswick)
Office of the Superintendent
of Securities (Prince Edward Island)
Office of the Superintendent
of Securities, Service Newfoundland and Labrador
Autorité des
marchés financiers
Re: | Technical Report (the “Report”)
entitled “Fortuna Silver Mines Inc: San Jose Mine, Oaxaca, Mexico” with
an effective date of December 31, 2023, prepared for Fortuna Silver Mines Inc. (the “Company”) |
I, the undersigned, a Qualified
Person as defined in National Instrument 43-101 – Standards of Disclosure for Mineral Projects, hereby consent to the public
filing of the Report by the Company.
“Patricia Gonzalez” | |
Patricia Gonzalez, MMSA (QP) | |
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