Xanadu Mines Ltd (
ASX: XAM, TSX: XAM)
(
Xanadu or the
Company) is
pleased to update the market on its on-going metallurgical test
program at the Kharmagtai Copper-Gold Project in the South Gobi
region of Mongolia.
Highlights
-
Preliminary metallurgical test work completed on partially oxidised
material from surface to 30 metres depth.
- Glycine
and cyanide leach tests delivered metallurgical recoveries
of up to 91% gold and 46% copper, with head grades ranging
between 0.52 g/t to 2.25 g/t Au and 0.12% to 0.67% Cu.
- All
partially oxidised material leached readily at a coarse
P80 > 2mm particle
size, indicating the potential for a heap leach
treatment.
- Indicates
a potential treatment path for approx. 90 million tonnes
(Mt) of oxidised material treated as waste in the
Scoping Study1 due to low flotation recovery.
- First
step in evaluating a material uplift opportunity identified in the
Scoping Study, to generate additional cash flow by leaching
partially oxidised, near surface material.
- Further
mineralogical studies required to confirm viability and optimise
the process.
Xanadu’s Executive Chairman & Managing Director, Colin
Moorhead said:
“These preliminary results are a very positive,
first step as we test the uplift opportunities in the Kharmagtai
Scoping Study. The base case assumed that all ore is processed
through a standard sulphide circuit, which means that the partially
oxidised material at the surface, which does not float, ends up
being treated as zero value waste. If we can turn that material
into cash generating ore by leaching with glycine and cyanide, it
has potential to drive significant value uplift for the Kharmagtai
project.”
Metallurgical Recoveries
Results from bottle roll tests at varying
cyanide and glycine addition rates were conducted using 2.5
kilograms per tonne (kg/t) cyanide and 2.5kg/t
glycine tests over a 48-hour conventional leach time, shown in
Table 1.
Table 1: Gold, silver and copper
recoveries at 2.5kg/t cyanide and 2.5kg/t glycine
addition
Sample |
Recovery (%) |
GoldAu |
CopperCu |
1 |
88.5 |
20.1 |
2 |
82.3 |
13.1 |
3 |
91.4 |
45.8 |
4 |
70.3 |
31.9 |
These results demonstrate achievement of high
gold recoveries at modest cyanide addition rates and in the
presence of significant cyanide soluble copper. The coarse particle
size indicates that heap leach treatment may be feasible.
Generally, gold leaching increases
with decreasing particle size, providing a larger
specific surface area for solution
contact. Gold recoveries are expected
to improve by grinding to 150 micrometre (µm)
particle size, typically used for Carbon in Leach
(CIL) processing.
Cyanide and glycine consumption was relatively
low, indicating high potential for recovering and recycling of both
reagents via the eventual optimal processing route. The addition of
glycine reduced the cyanide consumption versus the cyanide
consumption when leached using traditional cyanidation. Actual
cyanide consumption rates ranged from 1.6kg/t to 2.1kg/t.
Test Program Scope
There is up to 90Mt of partially oxidised
material at Kharmagtai, with 80% located near surface at Stockwork
Hill, White Hill and Golden Eagle. If this material was processed
as ore rather than pre-stripping, it could reduce waste rock
production by approx. 10%.
The scope of the test program included head
grade analysis and combined cyanide and glycine leach test work on
four composite samples of previously untested, partially oxidised
material from the upper 30m across the Kharmagtai mineralised
system. The objective of the leach tests was to determine
metallurgical recovery of gold and copper, and gauge potential of
glycine addition to enhance recovery and reduce cyanide
consumption. These results will inform future variability test work
to evaluate an optimal processing route for this material.
Leaching with Glycine and
Cyanide
Cyanide and glycine leaching was investigated on
this partially oxidised material. Low cyanide addition, coupled
with a glycine-dominant lixiviant, has many beneficial properties,
particularly for leaching of precious metals with elevated copper
content. This occurs due to copper preferentially
bonding to glycine rather than cyanide, thus freeing the cyanide to
leach gold.
Glycine is a widely available bulk reagent with
characteristics favourable for use in mineralogical processing;
non-toxic, water soluble, stable, non-volatile and can be recycled.
Under alkaline conditions, glycine forms stable complexes with
precious and base metals but not with iron, magnesium, or
manganese.
Metallurgical test work was undertaken by Perth
based Mining and Process Solutions (MPS), who hold
the rights for leaching metals using glycine with cyanide.
Sample Selection and
Preparation
Four composite samples were collected from
Stockwork Hill, White Hill and Golden Eagle deposits at Kharmagtai
project, as being representative of each of these zones. Samples
were coarse rejects (P80>2mm particle size), consisting of mixed
oxide and sulphide material taken from previously drilled diamond
core holes. There is a risk that aged
diamond core will deliver lower metallurgical recovery than test
work on newly drilled material, due to post-drilling oxidation.
Care was taken during sample selection to avoid those exhibiting
evidence of post-drilling oxidation.
Sample preparation consisted of homogenising and
splitting samples “as received” into their respective composites
and labelling “Sample 1” through to “Sample 4”, with no further
crushing or grinding. Each split was rotary split and homogenised
for head analysis and sub-samples taken for test work. Head assays
for Au, Silver (Ag) & Cu were conducted by
fire assay for each sample. Prior to
leach test work, samples were cured in 10k grams per tonne
(g/t) sulfuric acid for 24 hours to improve copper
extraction.
Metallurgical sample locations, zones and head
assay grades are detailed in Table 2. Drill hole
sample details are outlined in Table 3, and collar
locations for drill holes sampled are outlined in Figure
1.
Table 2: Metallurgical
sample details for partially oxidised test work
program
Sample |
Sample drill holes |
Zone |
Head assay grade |
g/t Au |
g/t Ag |
% Cu |
1 |
KHDDH393, KHDDH415, KHDDH491, KHDDH499 |
Stockwork Hill (South) |
2.25 |
3.0 |
0.66 |
2 |
KHDDH246, KHDDH266, KHDDH267, KHDDH359, KHDDH527 |
Stockwork Hill (North) |
0.95 |
2.0 |
0.67 |
3 |
KHDDH401, KHDDH514, KHDDH517, KHDDH518 |
Golden Eagle |
1.39 |
1.0 |
0.12 |
4 |
KHDDH230, KHDDH340, KHDDH437, KHDDH480, KHDDH489 |
White Hill |
0.52 |
2.0 |
0.45 |
Table 3: Drill hole sample details for
partially oxidised test work program
Hole ID |
Easting (m) |
Northing (m) |
Height (m) |
Azimuth (°) |
Dip (°) |
Sample True Depth (m) |
Start |
Finish |
KHDDH3932 |
592,455 |
4,877,833 |
1,288.22 |
101.50 |
-60 |
33 |
34 |
KHDDH415 |
592,486 |
4,877,834 |
1,288.06 |
123.00 |
-85 |
18 |
20 |
KHDDH491 |
592,523 |
4,877,822 |
1,287.63 |
0.00 |
-90 |
10 |
11 |
KHDDH499 |
592,504 |
4,877,828 |
1,287.89 |
0.00 |
-60 |
15 |
16 |
KHDDH246 |
592,580 |
4,877,983 |
1,289.00 |
0.00 |
-45 |
26 |
28 |
KHDDH266 |
592,491 |
4,877,988 |
1,289.00 |
0.00 |
-45 |
28 |
30 |
KHDDH2672 |
592,450 |
4,877,989 |
1,290.50 |
0.00 |
-45 |
32 |
34 |
KHDDH359 |
592,443 |
4,878,038 |
1,290.50 |
180.00 |
-68 |
18 |
20 |
KHDDH527 |
592,274 |
4,877,961 |
1,292.86 |
178.00 |
-72 |
28 |
30 |
KHDDH4011 |
595,402 |
4,876,996 |
1,268.52 |
216.00 |
-60 |
43 |
45 |
KHDDH5141 |
595,398 |
4,876,972 |
1,268.74 |
0.00 |
-90 |
46 |
47 |
KHDDH5171 |
595,423 |
4,877,025 |
1,268.59 |
0.00 |
-90 |
40 |
41 |
KHDDH5181 |
595,400 |
4,877,024 |
1,268.35 |
0.00 |
-90 |
45 |
46 |
KHDDH230 |
592,114 |
4,877,433 |
1,300.21 |
90.00 |
-50 |
16 |
18 |
KHDDH3402 |
592,023 |
4,877,266 |
1,309.38 |
5.00 |
-80 |
48 |
50 |
KHDDH437 |
591,914 |
4,877,472 |
1,299.00 |
205.00 |
-70 |
10 |
12 |
KHDDH480 |
592,200 |
4,877,398 |
1,300.43 |
0.00 |
-60 |
25 |
27 |
KHDDH489 |
592,005 |
4,877,400 |
1,303.00 |
215.00 |
-65 |
10 |
12 |
KHDDH491 |
592,455 |
4,877,833 |
1,288.22 |
101.50 |
-60 |
33 |
34 |
1 Golden Eagle has 25m barren cover overlaying
mineralisation, such that partially oxidised material commences at
25m true depth.2 Sample true depth exceeds 30m for each
of these drill holes given each deposit has a different depth from
surface to base of oxidation.
Figure 1: Collar locations for drill holes sampled in
metallurgical test work is available at
https://www.globenewswire.com/NewsRoom/AttachmentNg/7b028c5c-740b-476d-baed-ac6a2a481bc9
Future Test Work
Leaching of partially oxidised material will be
further investigated as follows:
-
Characterise partially oxidised material to quantify copper species
present.
-
Optimise cyanide and glycine reagent addition to maximise
metallurgical recovery and minimise cyanide consumption.
-
Undertake variability test work across the mineralised partially
oxidised zones to understand leaching kinetics.
-
Undertake grind variability assessment as part of glycine and
cyanide leaching to understand liberation and maximum achievable
metal recovery.
-
Determine suitable flowsheet options.
Partially oxidised material test work is a
subset of the broader Kharmagtai metallurgical test work program. A
comprehensive metallurgy program during the Pre-Feasibility Study
over next 12 to 18 months will investigate flotation and
comminution properties of the mineralisation and alteration styles
at Kharmagtai, aiming to determine optimum flowsheet and generate
inputs for engineering design. This will also generate data to
inform the copper and gold recovery models, and allow operating
costs estimates to be calculated. Concentrate samples will be
generated for marketing studies as part of the broader metallurgy
program.
About Xanadu Mines
Xanadu is an ASX and TSX listed Exploration
company operating in Mongolia. We give investors exposure to
globally significant, large-scale copper-gold discoveries and
low-cost inventory growth. Xanadu maintains a portfolio of
exploration projects and remains one of the few junior explorers on
the ASX or TSX who control a globally significant copper-gold
deposit in our flagship Kharmagtai project. For information on
Xanadu visit: www.xanadumines.com.
Colin MoorheadExecutive Chairman & Managing
DirectorXanadu Mines Ltdinfo@xanadumines.com+61 2 8280 7497
This Announcement was authorised for release by
Xanadu’s Executive Chairman & Managing Director.
Appendix 1: Statements and
Disclaimers
Competent Person Statements
The information in this Announcement that
relates to exploration results is based on information compiled by
Dr Andrew Stewart, who is responsible for the exploration data,
comments on exploration target sizes, QA/QC and geological
interpretation and information. Dr Stewart, who is an employee of
Xanadu and is a Member of the Australasian Institute of
Geoscientists, has sufficient experience relevant to the style of
mineralisation and type of deposit under consideration and to the
activity he is undertaking to qualify as the “Competent Person” as
defined in the 2012 Edition of the Australasian Code for Reporting
Exploration Results, Mineral Resources and Ore Reserves and the
National Instrument 43-101. Dr Stewart consents to the inclusion in
the report of the matters based on this information in the form and
context in which it appears.
The information in this Announcement that
relates to metallurgy and metallurgical test work has been reviewed
by Andrew Goulsbra, AusIMM, B.App Sci (Met). Mr Goulsbra is not an
employee of the Company but is employed as a contract consultant.
Mr Goulsbra is a member of the Australasian Institute of Mining and
Metallurgy; he has sufficient experience with the style of
processing response and type of deposit under consideration, and to
the activities undertaken, to qualify as a competent as defined in
the 2012 Edition of the Australasian Code for Reporting Exploration
Results, Mineral Resources and Ore Reserves and the National
Instrument 43-101. Mr Goulsbra consents to the inclusion in this
report of the contained technical information in the form and
context as it appears.
Forward-Looking Statements
Certain statements contained in this
Announcement, including information as to the future financial or
operating performance of Xanadu and its projects may also include
statements which are ‘forward‐looking statements’ that may include,
amongst other things, statements regarding targets, estimates and
assumptions in respect of mineral reserves and mineral resources
and anticipated grades and recovery rates, production and prices,
recovery costs and results, capital expenditures and are or may be
based on assumptions and estimates related to future technical,
economic, market, political, social and other conditions. These
‘forward-looking statements’ are necessarily based upon a number of
estimates and assumptions that, while considered reasonable by
Xanadu, are inherently subject to significant technical, business,
economic, competitive, political and social uncertainties and
contingencies and involve known and unknown risks and uncertainties
that could cause actual events or results to differ materially from
estimated or anticipated events or results reflected in such
forward‐looking statements.
Xanadu disclaims any intent or obligation to
update publicly or release any revisions to any forward‐looking
statements, whether as a result of new information, future events,
circumstances or results or otherwise after the date of this
Announcement or to reflect the occurrence of unanticipated events,
other than required by the Corporations Act 2001 (Cth) and the
Listing Rules of the Australian Securities Exchange
(ASX) and Toronto Stock Exchange
(TSX). The words ‘believe’, ‘expect’,
‘anticipate’, ‘indicate’, ‘contemplate’, ‘target’, ‘plan’,
‘intends’, ‘continue’, ‘budget’, ‘estimate’, ‘may’, ‘will’,
‘schedule’ and similar expressions identify forward‐looking
statements.
All ‘forward‐looking statements’ made in this
Announcement are qualified by the foregoing cautionary statements.
Investors are cautioned that ‘forward‐looking statements’ are not
guarantee of future performance and accordingly investors are
cautioned not to put undue reliance on ‘forward‐looking statements’
due to the inherent uncertainty therein.
For further information please visit the Xanadu
Mines’ Website at www.xanadumines.com.
Appendix 2: Kharmagtai Table 1 (JORC
Code, 2012)
Set out below is Section 1 and Section 2 of
Table 1 under the JORC Code, 2012 Edition for the Kharmagtai
project. Data provided by Xanadu. This Table 1 updates the JORC
Table 1 disclosure dated 8 December 2021.
JORC TABLE 1, SECTION 1 - SAMPLING
TECHNIQUES & DATA
(Criteria in this section apply to all succeeding sections).
Criteria |
Commentary |
Sampling techniques |
- Sampling
techniques reported herein are described in detail in the text of
this report
- Representative ½
core samples were split from PQ, HQ & NQ diameter diamond drill
core on site using rock saws, on a routine 2m sample interval that
also honours lithological/intrusive contacts.
- The orientation
of the cut line is controlled using the core orientation line
ensuring uniformity of core splitting wherever the core has been
successfully oriented.
- Sample intervals
are defined and subsequently checked by geologists, and sample tags
are attached (stapled) to the plastic core trays for every sample
interval.
- Reverse
Circulation (RC) chip samples are ¼ splits from
one meter (1m) intervals using a 75%:25% riffle
splitter to obtain a 3kg sample
- RC samples are
uniform 2m samples formed from the combination of two ¼ split 1m
samples.
|
Drilling techniques |
- The Mineral
Resource Estimation and metallurgical sampling has been based upon
diamond drilling of PQ, HQ and NQ diameters with both standard and
triple tube core recovery configurations, RC drilling and surface
trenching with channel sampling.
- All drill core
drilled by Xanadu has been oriented using the “Reflex Ace”
tool.
|
Drill sample recovery |
- Diamond drill
core recoveries were assessed using the standard industry (best)
practice which involves removing the core from core trays;
reassembling multiple core runs in a v-rail; measuring core lengths
with a tape measure, assessing recovery against core block depth
measurements and recording any measured core loss for each core
run.
- Diamond core
recoveries average 97% through mineralisation.
- Overall, core
quality is good, with minimal core loss. Where there is localised
faulting and or fracturing core recoveries decrease, however, this
is a very small percentage of the mineralised intersections.
- RC recoveries
are measured using whole weight of each 1m intercept measured
before splitting
- Analysis of
recovery results vs grade shows no significant trends that might
indicate sampling bias introduced by variable recovery in
fault/fracture zones.
|
Logging |
- All drill core
is geologically logged by well-trained geologists using a modified
“Anaconda-style” logging system methodology. The Anaconda method of
logging and mapping is specifically designed for porphyry Cu-Au
mineral systems and is entirely appropriate to support Mineral
Resource Estimation, mining and metallurgical studies.
- Logging of
lithology, alteration and mineralogy is intrinsically qualitative
in nature. However, the logging is subsequently supported by 4 Acid
ICP-MS (48 element) geochemistry and SWIR spectral mineralogy
(facilitating semi-quantitative/calculated mineralogical,
lithological and alteration classification) which is integrated
with the logging to improve cross section interpretation and 3D
geological model development.
- Drill core is
also systematically logged for both geotechnical features and
geological structures. Where drill core has been successfully
oriented, the orientation of structures and geotechnical features
are also routinely measured.
- Both wet and dry
core photos are taken after core has been logged and marked-up but
before drill core has been cut.
|
Sub-sampling techniques and sample
preparation |
- All drill core
samples are ½ core splits from either PQ, HQ or NQ diameter cores.
A routine 2m sample interval is used, but this is varied locally to
honour lithological/intrusive contacts. The minimum allowed sample
length is 30cm.
- Core is
appropriately split (onsite) using diamond core saws with the cut
line routinely located relative to the core orientation line (where
present) to provide consistency of sample split selection.
- The diamond saws
are regularly flushed with water to minimize potential
contamination.
- A field
duplicate ¼ core sample is collected every 30th sample to
ensure the “representivity of the in-situ material collected”. The
performance of these field duplicates is routinely analysed as part
of Xanadu’s sample QC process.
- Routine sample
preparation and analyses of DDH samples were carried out by ALS
Mongolia LLC (ALS Mongolia), who operates an
independent sample preparation and analytical laboratory in
Ulaanbaatar.
- All samples were
prepared to meet standard quality control procedures as follows:
Crushed to 75% passing 2mm, split to 1kg, pulverised to 85% passing
200 mesh (75 microns) and split to 150g sample pulp.
- ALS Mongolia
Geochemistry labs quality management system is certified to ISO
9001:2008.
- The sample
support (sub-sample mass and comminution) is appropriate for the
grainsize and Cu-Au distribution of the porphyry Cu-Au
mineralization and associated host rocks.
- Sample
preparation at Mining And mineral Process Solutions (MPS), Perth,
consisted of homogenising and splitting samples “as received” into
their respective composites and labelling them “Sample 1” through
to “Sample 4”. Each split was then rotary split and homogenised for
head analysis and sub-samples were taken for testwork.
|
Quality of assay data and laboratory tests |
- All samples were
routinely assayed by ALS Mongolia for gold
- Au is determined
using a 25g fire assay fusion, cupelled to obtain a bead, and
digested with Aqua Regia, followed by an atomic absorption
spectroscopy (AAS) finish, with a lower detection
(LDL) of 0.01 ppm.
- All samples were
also submitted to ALS Mongolia for the 48-element package ME-ICP61
using a four-acid digest (considered to be an effective total
digest for the elements relevant to the Mineral Resource Estimate
(MRE)). Where copper is over-range (>1% Cu), it
is analysed by a second analytical technique (Cu-OG62), which has a
higher upper detection limit (UDL) of 5%
copper.
- Quality
assurance has been managed by insertion of appropriate Standards
(1:30 samples – suitable Ore Research Pty Ltd certified standards),
Blanks (1:30 samples), Duplicates (1:30 samples – ¼ core duplicate)
by Xanadu.
- Assay results
outside the optimal range for methods were re-analysed by
appropriate methods.
- Ore Research Pty
Ltd certified copper and gold standards have been implemented as a
part of QC procedures, as well as coarse and pulp blanks, and
certified matrix matched copper-gold standards.
- QC monitoring is
an active and ongoing processes on batch by batch basis by which
unacceptable results are re-assayed as soon as practicable.
- Prior to 2014:
Cu, Ag, Pb, Zn, As and Mo were routinely determined using a
three-acid-digestion of a 0.3g sub-sample followed by an AAS finish
(AAS21R) at SGS Mongolia. Samples were digested with nitric,
hydrochloric and perchloric acids to dryness before leaching with
hydrochloric acid to dissolve soluble salts and made to 15ml volume
with distilled water. The LDL for copper using this technique was
2ppm. Where copper was over-range (>1% Cu), it was analysed by a
second analytical technique (AAS22S), which has a higher upper
detection limit (UDL) of 5% copper. Gold analysis method was
essentially unchanged.
- All
metallurgical testwork assays were carried out at ALS, Perth. Gold
and copper solid assays were determined using Fire Assay followed
by AAS. Solution assays were determined using AAS.
|
Verification of sampling and assaying |
- All assay data
QA/QC is checked prior to loading into Xanadu’s Geobank data
base.
- The data is
managed by Xanadu geologists.
- The data base
and geological interpretation is managed by Xanadu.
- Check assays are
submitted to an umpire lab (SGS Mongolia) for duplicate
analysis.
- No twinned drill
holes exist.
- There have been
no adjustments to any of the assay data.
|
Location of data points |
- Diamond drill
holes have been surveyed with a differential global positioning
system (DGPS) to within 10cm accuracy.
- The grid system
used for the project is UTM WGS-84 Zone 48N
- Historically,
Eastman Kodak and Flexit electronic multi-shot downhole survey
tools have been used at Kharmagtai to collect down hole azimuth and
inclination information for the majority of the diamond drill
holes. Single shots were typically taken every 30m to 50m during
the drilling process, and a multi-shot survey with readings every
3-5m are conducted at the completion of the drill hole. As these
tools rely on the earth’s magnetic field to measure azimuth, there
is some localised interference/inaccuracy introduced by the
presence of magnetite in some parts of the Kharmagtai mineral
system. The extent of this interference cannot be quantified on a
reading-by-reading basis.
- More recently
(since September 2017), a north-seeking gyro has been employed by
the drilling crews on site (rented and operated by the drilling
contractor), providing accurate downhole orientation measurements
unaffected by magnetic effects. Xanadu have a permanent calibration
station setup for the gyro tool, which is routinely calibrated
every 2 weeks (calibration records are maintained and were
sighted)
- The project
Digital Terrain Model (DTM) is based on 1m
contours from satellite imagery with an accuracy of ±0.1 m.
|
Data spacing and distribution |
- Holes spacings
range from <50m spacings within the core of mineralization to
+500m spacings for exploration drilling. Hole spacings can be
determined using the sections and drill plans provided.
- Holes range from
vertical to an inclination of -60 degrees depending on the attitude
of the target and the drilling method.
- The data spacing
and distribution is sufficient to establish anomalism and targeting
for porphyry Cu-Au, tourmaline breccia and epithermal target
types.
- Holes have been
drilled to a maximum of 1,400m vertical depth.
- The data spacing
and distribution is sufficient to establish geological and grade
continuity, and to support the Mineral Resource
classification.
|
Orientation of data in relation to geological
structure |
- Drilling is
conducted in a predominantly regular grid to allow unbiased
interpretation and targeting.
- Scissor
drilling, as well as some vertical and oblique drilling, has been
used in key mineralised zones to achieve unbiased sampling of
interpreted structures and mineralised zones, and in particular to
assist in constraining the geometry of the mineralised hydrothermal
tourmaline-sulphide breccia domains.
|
Sample security |
- Samples are
delivered from the drill rig to the core shed twice daily and are
never left unattended at the rig.
- Samples are
dispatched from site in locked boxes transported on Xanadu company
vehicles to ALS lab in Ulaanbaatar.
- Sample shipment
receipt is signed off at the Laboratory with additional email
confirmation of receipt.
- Samples are then
stored at the lab and returned to a locked storage site.
|
Audits or reviews |
- Internal audits
of sampling techniques and data management are undertaken on a
regular basis, to ensure industry best practice is employed at all
times.
- External reviews
and audits have been conducted by the following groups:
- 2012: AMC
Consultants Pty Ltd. was engaged to conduct an Independent
Technical Report which reviewed drilling and sampling procedures.
It was concluded that sampling and data record was to an
appropriate standard.
- 2013: Mining
Associates Ltd. was engaged to conduct an Independent Technical
Report to review drilling, sampling techniques and QA/QC. Methods
were found to conform to international best practice.
- 2018: CSA Global
reviewed the entire drilling, logging, sampling, sample shipping
and laboratory processes during the competent persons site visit
for the 2018 Mineral Resource Estimate and found the systems and
adherence to protocols to be to an appropriate standard.
|
JORC TABLE 1, SECTION 2 - REPORTING OF
EXPLORATION RESULTS
(Criteria in this section apply to all succeeding sections).
Criteria |
Commentary |
Mineral tenementand land tenure
status |
- The Project comprises 2 Mining
Licences (MV-17129A Oyut Ulaan and (MV-17387A Kharmagtai):
- Xanadu now owns 100% of Vantage
LLC, the 100% owner of the Oyut Ulaan mining licence.
- The Kharmagtai mining license
MV-17387A is 100% owned by Oyut Ulaan LLC. Xanadu has an 85%
interest in Mongol Metals LLC, which has 90% interest in Oyut Ulaan
LLC. The remaining 10% in Oyut Ulaan LLC is owned by Quincunx (BVI)
Ltd (“Quincunx”).
- The Mongolian Minerals Law
(2006) and Mongolian Land Law (2002) govern
exploration, mining and land use rights for the project.
|
Exploration done by other parties |
- Previous exploration at Kharmagtai
was conducted by Quincunx Ltd, Ivanhoe Mines Ltd and Turquoise Hill
Resources Ltd including extensive drilling, surface geochemistry,
geophysics, mapping.
- Previous exploration at Red
Mountain (Oyut Ulaan) was conducted by Ivanhoe Mines.
|
Geology |
- The mineralisation is characterised
as porphyry copper-gold type.
- Porphyry copper-gold deposits are
formed from magmatic hydrothermal fluids typically associated with
felsic intrusive stocks that have deposited metals as sulphides
both within the intrusive and the intruded host rocks. Quartz
stockwork veining is typically associated with sulphides occurring
both within the quartz veinlets and disseminated thought out the
wall rock. Porphyry deposits are typically large tonnage deposits
ranging from low to high grade and are generally mined by large
scale open pit or underground bulk mining methods. The deposits at
Kharmagtai are atypical in that they are associated with
intermediate intrusions of diorite to quartz diorite composition;
however, the deposits are in terms of contained gold significant,
and similar gold-rich porphyry deposits.
|
Drill hole information |
- Diamond drill holes are the
principal source of geological and grade data for the Project.
- See figures in this ASX/TSX
Announcement.
|
Data aggregation methods |
- A nominal cut-off of 0.1% copper
equivalent (CuEq) is used in copper dominant
systems for identification of potentially significant intercepts
for reporting purposes. Higher grade cut-offs are 0.3%, 0.6% and 1%
CuEq.
- A nominal cut-off of 0.1g/t gold
equivalent (AuEq) is used in gold dominant systems
like Golden Eagle for identification of potentially significant
intercepts for reporting purposes. Higher grade cut-offs are
0.3g/t, 0.6g/t and 1g/t AuEq.
- Maximum contiguous dilution within
each intercept is 9m for 0.1%, 0.3%, 0.6% and 1% CuEq.
- Most of the reported intercepts are
shown in sufficient detail, including maxima and subintervals, to
allow the reader to make an assessment of the balance of high and
low grades in the intercept.
- Informing samples have been
composited to two metre lengths honouring the geological domains
and adjusted where necessary to ensure that no residual sample
lengths have been excluded (best fit).
The copper equivalent
(CuEq or eCu)
calculation represents the total metal value for each metal,
multiplied by the conversion factor, summed and expressed in
equivalent copper percentage with a metallurgical recovery factor
applied.Copper equivalent
(CuEq or eCu) grade
values were calculated using the following formula:
CuEq or eCu = Cu + Au * 0.60049 * 0.86667,Gold equivalent
(AuEq or eAu) grade
values were calculated using the following formula:
AuEq or eAu = Au + Cu / 0.60049 * 0.86667.Where: Cu - copper grade
(%), Au - gold grade (g/t), 0.60049 - conversion factor (gold to
copper), 0.86667 - relative recovery of gold to copper (86.67%)The
copper equivalent formula was based on the following parameters
(prices are in USD):
- Copper price - 3.4 $/lb
- Gold
price - 1400
$/oz
- Copper recovery - 90%
- Gold recovery - 78%
- Relative recovery of gold to copper
= 78% / 90% = 86.67%.
|
Relationship between mineralisation on widths and
interceptLengths |
- Mineralised structures are variable
in orientation, and therefore drill orientations have been adjusted
from place to place in order to allow intersection angles as close
as possible to true widths.
- Exploration results have been
reported as an interval with 'from' and 'to' stated in tables of
significant economic intercepts. Tables clearly indicate that true
widths will generally be narrower than those reported.
|
Diagrams |
- See figures in the body of this
ASX/TSX Announcement.
|
Balanced reporting |
- Resources have been reported at a
range of cut-off grades, above a minimum suitable for open pit
mining, and above a minimum suitable for underground mining.
- All metallurgical results are
presented.
|
Other substantiveExploration
data |
- Extensive work in this area has
been done and is reported separately.
|
Further Work |
- The mineralisation is open at depth
and along strike.
- Current estimates are restricted to
those expected to be reasonable for open pit mining. Limited
drilling below this depth (-300m relative level
(mRL) shows widths and grades potentially suitable
for underground extraction.
- Exploration on going.
|
JORC TABLE 1, SECTION 3 - ESTIMATION
& REPORTING OF MINERAL RESOURCES
Mineral Resources are not reported so Section 4
is not applicable to this Announcement.
JORC TABLE 1, SECTION 4 - ESTIMATION
& REPORTING OF ORE RESERVES
Ore Reserves are not reported so Section 4 is
not applicable to this Announcement.
______________________________1 ASX/TSX
Announcement, 6 April 2022 - Scoping Study - Kharmagtai Copper-Gold
Project
Xanadu Mines (TSX:XAM)
Historical Stock Chart
From Mar 2024 to Apr 2024
Xanadu Mines (TSX:XAM)
Historical Stock Chart
From Apr 2023 to Apr 2024