TIDMBSE
AIM and Media Release
19 February 2021
BASE RESOURCES LIMITED
Updated Kwale North Dune and Maiden Bumamani Mineral Resources Estimates
Key Points
* As part of the pre-feasibility study currently underway to assess the
viability of mining the Kwale North Dune and Bumamani deposits, seeking to
extend the mine life of Kwale Operations, additional drilling and
mineralogy assessments have been conducted.
* The Kwale North Dune Mineral Resources estimate has increased by 13% to 194
million tonnes at an average HM grade of 1.5%, containing 2.9Mt HM, based
on a 1% HM cut-off grade.
* 99% of the Kwale North Dune Mineral Resources estimate is now reported in
the Measured and Indicated categories.
* The maiden Bumamani Mineral Resources estimate is 5.9 million tonnes at an
average HM grade of 1.9%, containing 0.115Mt HM, based on a 1% HM cut-off
grade.
* The pre-feasibility study for the Kwale North Dune and Bumamani deposits is
due for completion early in Q2 2021.
African mineral sands producer, Base Resources Limited (ASX / AIM: BSE) (Base
Resources) is pleased to provide an update to the Kwale North Dune Mineral
Resources (2021 Kwale North Dune Mineral Resources) estimate and announce a
maiden Bumamani Mineral Resources estimate (2021 Bumamani Mineral Resources) at
its 100% owned and operated mineral sands operations in Kwale County, Kenya (
Kwale Operations).
The 2021 Kwale North Dune Mineral Resources and 2021 Bumamani Mineral Resources
estimates are being presented together because of the close proximity of the
underlying deposits and as these deposits are the subject of a single
pre-feasibility study (the Kwale North Dune PFS) being undertaken to assess
their potential to extend the mine life of Kwale Operations. The Kwale North
Dune PFS commenced in early 2020 and is due for completion early in the second
quarter of 2021.
Since announcement of the maiden JORC 2012 North Dune Mineral Resources
estimate in May 2019 (2019 Kwale North Dune Mineral Resources)1, Base Resources
has carried out additional drilling, assaying and mineralogy studies of the
Kwale North Dune to improve the confidence of the Mineral Resources estimate
and further the Company's understanding of the deposit. As a result of this
additional work, 99% of the 2021 Kwale North Dune Mineral Resources estimate is
now reported in the Measured and Indicated categories. Material tonnage for
the 2021 Kwale North Dune Mineral Resources estimate has also increased by 13%
and contained heavy mineral (HM) has increased by 12% from the 2019 Kwale North
Dune Mineral Resources estimate.
The 2021 Kwale North Dune Mineral Resources are now estimated to be 194 million
tonnes (Mt) at an average HM grade of 1.5% for 2.9Mt of contained HM, at a 1%
HM cut-off grade.
The Bumamani deposit is situated approximately 1.5km south of the North Dune
deposit (Figure 1) and was discovered by Base Resources in 2017 when drilling
to test for mineralisation in the north-east sector of the Kwale Prospecting
Licence PL/2018/0119 (PL119). At that time, taking into account the results at
hand and the small size of the deposit indicated by such results, it was
decided that any Mineral Resources estimate would be deferred until the full
drilling program planned for the north-east sector was able to be completed and
the full results incorporated into the estimation process. Due to ongoing
community access issues, Base Resources has not been able to complete that
program. However, with commencement of the Kwale North Dune PFS, the Bumamani
deposit has now been revisited due to its proximity to the Kwale North deposit
and a Mineral Resources estimate completed to allow its inclusion in that
study.
The maiden 2021 Bumamani Mineral Resources estimate was developed from 2,977.5m
of drilling from 183 holes and is 5.9Mt at an average HM grade of 1.9% for
0.115Mt of contained HM, at a 1% HM cut-off grade.
The 2021 Kwale North Dune Mineral Resources and the 2021 Bumamani Mineral
Resources estimates are reported in accordance with the JORC Code. Base
Resources has a net attributable interest of 100% in the 2021 Kwale North Dune
Mineral Resources and the 2021 Bumamani Mineral Resources.
The information prescribed by the ASX Listing Rules, including a summary of the
information material to understanding each Mineral Resources estimate in
respect of the prescribed matters, is set out in the sections below. For each
Mineral Resources estimate, such information should be read in conjunction with
the explanatory information provided in respect of the applicable estimate for
the purposes of Sections 1 to 3 of Table 1 of the JORC Code - see Appendix 1 to
this announcement in the case of the 2021 Kwale North Dune Mineral Resources
estimate and Appendix 2 in the case of the 2021 Bumamani Mineral Resources
estimate.
Figures (graphics) referenced in this announcement have been omitted. A full
PDF version of this announcement, including all figures (graphics), is
available from Base Resources' website: https://baseresources.com.au/investors
/ announcements/.
[Note (1): Refer to Base Resources' market announcement "Mineral Resource for
Kwale North Dune deposit" released on 1 May 2019, which is available at https:/
/baseresources.com.au/investors/announcements/]
Table 1: 2021 Kwale North Dune Mineral Resources estimate compared with the
2019 Kwale North Dune Mineral Resources estimate.
2021 2019
as at 19 February 2021 as at 1 May 2019
HM Assemblage HM Assemblage
Tonnes HM HM SL OS Tonnes HM HM SL OS
Category (Mt) (Mt) (%) (%) (%) (Mt) (Mt) (%) (%) (%)
ILM RUT ZIR ILM RUT ZIR
(%) (%) (%) (%) (%) (%)
Kwale North Dune Mineral Resources
Measured 119 1.8 1.5 37 1 42 13 6 - - - - - - - -
Indicated 73 1.0 1.4 37 2 50 14 6 136 2.1 1.5 38 2 45 12 5
Inferred 2 0.0 1.2 37 3 50 15 7 34 0.5 1.4 36 3 46 13 6
Total 194 2.9 1.5 37 2 45 13 6 171 2.6 1.5 38 2 45 12 5
Table subject to rounding differences, resources estimated at a 1% HM cut-off
grade.
Table 2: Maiden 2021 Bumamani Mineral Resources estimate.
2021
as at 19 February 2021
HM Assemblage HM Assemblage
Tonnes HM HM SL OS Tonnes HM HM SL OS
Category (Mt) (kt) (%) (%) (%) (Mt) (Mt) (%) (%) (%)
ILM RUT ZIR ILM RUT ZIR
(%) (%) (%) (%) (%) (%)
Bumamani Mineral Resources
Measured 3.0 66 2.2 19 2 48 15 7.5
Indicated 2.6 45 1.7 23 5 47 16 7.7
N/A
Inferred 0.3 4 1.4 27 6 41 14 7.8
Total 5.9 115 1.9 21 4 47 15 7.6
Table subject to rounding differences, resources estimated at a 1% HM cut-off
grade.
Further information relevant to both Mineral Resources estimates
Kwale Operations is located on Special Mining Lease 23 (SML 23), which lies
within PL119. The Prospecting Licence covers an area of 88.7km2, which
includes the Kwale North and Bumamani deposits, and is located approximately 50
kilometres south of Mombasa and approximately 10 kilometres inland from the
Kenyan coast (Figure 1).
The Kwale Project initially comprised three areas that contained concentrations
of heavy minerals. They were the South Dune, Central Dune (now totally
depleted by mining and currently the repository for sand tailings from the
South Dune) and the North Dune deposits (Figure 2), with the Bumamani deposit
only being discovered in 2017 after mining operations had commenced.
The project was initially owned by Tiomin Resources Inc. (Tiomin) which
conducted drilling in 1997 and then by Base Titanium Limited (a wholly owned
subsidiary of Base Resources) which purchased the project late in 2010 and
commenced confirmatory drilling of the Central, South and North Dune deposits.
The North Dune deposit was initially excluded from the project's Mineral
Resources on the basis of HM grade and the then prevailing economic
conditions. However, in 2018, it was decided to re-evaluate the potential of
the North Due in light of improved economic conditions, refined resource
definition methodology and with insights gained from five years of operations
on the Central Dune. Following that decision, the 2019 Kwale North Dune
Mineral Resources estimate was announced.
The rocks of the area are of sedimentary origin and range in age from Upper
Carboniferous to Recent. Three divisions are recognised: the Cainozoic rocks,
the Upper Mesozoic rocks (not exposed within the area) and the Duruma Sandstone
Series giving rise to the dominant topographical feature of the area: the
Shimba Hills. The Shimba grits and Mazeras sandstone are of Upper Triassic age
and form the Upper Duruma Sandstone.
The Magarini sands form a belt of low hills running parallel to the coast.
They rest with slight unconformity on the Shimba grits and Mazeras sandstone.
This formation was deposited during Pliocene times and consists mainly of
unconsolidated fluviatile sediments derived from the Duruma Sandstone Series.
The Kwale deposits are an aeolian subset of the Magarini sands and are
generally poorly stratified and contain a fraction of clay, which for the North
Dune and Bumamani deposits is approximately 37% and 21%, respectively. Heavy
minerals, mainly ilmenite, rutile and zircon, are locally concentrated and are
abundant in some places, giving rise to the deposits.
Further information specific to the 2021 Kwale North Dune Mineral Resources
estimate
The geological interpretations for the Kwale North Dune deposit considered the
data in the drill logs, HM assay results, microscopic logging of HM sinks,
detailed mineralogy and knowledge gained from mining the Central Dune and South
Dune deposits. Four geological domains have been identified at the Kwale North
Dune deposit. These were used and honoured during the geological modelling
(Figure 3).
The uppermost zone at the Kwale North Dune deposit, referred to as Ore Zone 1,
is a dark brown, predominantly fine grained, well sorted silty sand with very
little induration and is similar to the Ore Zone 1 units in the other Kwale
deposits. Mineralogically, it is characterised by clean, glossy and rounded HM
grains with an average valuable heavy mineral (VHM) content of approximately
75%.
Ore Zone 4 lies below Ore Zone 1, with an indurated paleo-surface separating
the two zones, as observed in the field through difficult drill bit
penetration, and in HM sink logs, exhibiting elevated iron oxides. The Ore
Zone 4 host is higher in slimes with difficult washability and the grain
sorting is generally poor. It is slightly lower in VHM content (71%), often
with elevated iron oxides and alumino-silicate minerals (kyanite, andalusite
and sillimanite). Ore Zone 4 is considered a fluvial deposit based on the
difficulty of wash and the poor grain sorting.
Ore Zone 5 lies below Ore Zone 4 and is separated from that zone by a lateritic
paleo-surface and is also hosted in a fluviatile clay-rich, poorly sorted
formation. It is distinguished mineralogically by an increased amount of
almandine garnet that reports to the magnetic fraction, significantly
increasing magnesium, manganese, aluminium and silicon in the oxide chemistry.
As a result of this, Ore Zone 5 has a notably lower average VHM content (44%).
The Basement Zone lies below Ore Zone 5 and is typically hosted in weathered
variants of the Mesozoic (Permo-Triassic) Duruma Sandstones. It does contain
mineralisation which was reported in the 2019 Kwale North Dune Mineral
Resources estimate as Ore Zone 10. However, it has a VHM content of just 10%
being predominantly titano-haematite (<40% TiO2) to which no value is ascribed,
with zircon enrichment in the non-magnetic fraction. This mineralisation was
assessed at scoping level. It is not considered to hold potential for eventual
economic extraction due to its low VHM content, depth of burial, high slime
content (42%), high grade variability, presence of induration and the fact that
most of it lies below the water table (significantly increasing the cost and
complexity of mining) and is therefore not reported.
For Ore Zones 1, 4 and 5, a strong correlation between the field logs, HM sink
logs and XRF oxide chemistry and QEMSCAN mineralogy gives confidence to these
interpretations.
Following acquisition of the Kwale Project, subsequent resource drilling by
Base Resources' wholly-owned subsidiary, Base Titanium Limited, of the Kwale
North deposit was completed using the reverse circulation, air core (RCAC)
method and conducted in three campaigns: November 2010, December 2012 to April
2013 and June 2018 to May 2019 (Figure 4). A total of 745 holes were drilled
for 27,429 metres and generated 15,441 samples for assay. Tiomin drilled 37
holes in 1997 but, due to poor twinned hole assay repeatability at other areas
of the Kwale Project, no Tiomin drilling information was used by Base Resources
for the 2019 Kwale North Dune Mineral Resources estimate and this is also the
case of the 2021 Kwale North Dune Mineral Resources.
The predominantly three metre sample intervals in the 2010 and 2012/13 drilling
were replaced by sampling at 1.5 metre intervals for the 2018/19 drill program
to provide greater control on geological boundaries. Sample sizes averaged
close to 3kg at this sample interval when collecting 25% of the rotary splitter
cycle. Samples were dried, weighed, and screened for material less than 45
micrometres (slimes) and +1 mm (oversize).
Approximately 100 grams of the screened sample was subjected to a HM float/sink
technique using the heavy liquid, lithium polytungstate (LST) with a specific
gravity of 2.85 grams per cubic centimetre. The resulting HM concentrate was
dried and weighed as were the other separated constituent size fractions (the
minus 45 micrometre material being calculated by difference).
Mineral assemblage analyses were conducted by Base Resources to characterise
the mineralogical and chemical characteristics of specific mineral species and
magnetic fractions. These mineral assemblage samples were subjected to
magnetic separation using a Mineral Technologies induced-roll magnetic
separator which captures magnetic (mag), middling (mid) and non-magnetic (
non-mag) fractions. The mid and mag fractions were combined and, with the
non-mag fraction, were subjected to XRF analysis using a Bruker, S8 Tiger XRF.
Data from the mag and non-mag XRF analyses are processed through an algorithm (
Minmod) that runs approximately 100,000 iterations in assigning key chemical
species to derive a calculated mineralogy determination.
Drill hole collar and geology data was captured by industry-specific, field
logging software with on-board validation. Field and assay data were managed
in a MS Access database and subsequently migrated to a more secure SQL
database.
Standard samples were generated and certified for use in the field and
laboratory. Accuracy of HM and slimes (SL) analysis was verified by using the
standard samples and monitored using control charts. Standard errors greater
than three standard deviations from the mean prompted batch re-assay. A
standard precision analysis was conducted on the key assay fields: HM, SL and
Oversize (OS) for both laboratory and field duplicate samples. Normal scatter
and QQ plots were prepared for HM, SL and OS for laboratory and field
duplicates.
A twin drilling program was introduced for the 2018 program to quantify
short-range variability in geological character and grade intersections. A
water injection versus dry drilling assessment was included in the twin
drilling analysis. Field and laboratory duplicate, standard and twin drilling
analysis show adequate level of accuracy and precision to support resource
classifications as stated.
A topographic DTM was prepared by Base Resources based on a LIDAR survey.
Construction of the geological grade model was based on coding model cells
below open wireframe surfaces, comprising topography, geology (Ore Zones 1, 4,
and 5) and basement (Figure 3). Model cell dimensions of 50m x 50m x 1.5m in
the XYZ orientations were utilised.
Interpolation was undertaken using various sized search ellipses to populate
the model with primary grade fields (HM, SL and OS), and index fields
(hardness, induration percent, mineralogy). Inverse distance weighting to a
power of three was used for primary assay fields whilst nearest neighbour was
used to interpolate index fields. Figure 5 shows an oblique view of the model
coloured by HM grades.
A fixed bulk density of 1.7 (t/m3) was applied to the 2021 Kwale North Dune
Mineral Resources model. This bulk density was selected based on operational
experience in the Kwale Central and South Dune deposits and because no bulk
density sampling was undertaken. This is considered to be a conservative
estimate of bulk density.
The Kwale North Dune deposit, being similar in nature to the Kwale South Dune
deposit currently being mined, is considered amenable to being mined and
processed in the same way. That is, by using the existing plant and equipment
at the Kwale Operations: hydraulic mining, spiral concentrator and mineral
separation plant with magnetic, electrostatic and further gravity separation.
The only departure from current methodology is that, for the Kwale North Dune
deposit, the fine and coarse tailings are likely to be co-disposed together.
Apart from that, there is no indication that the mining, metallurgical and
operating cost modifying factors for the Kwale North deposit would be
materially different to those derived from mining the Kwale South Dune
deposit.
The criteria used for classification was primarily the drill spacing
(predominantly 100m x 100m) and sample interval (predominantly 1.5m), with
consideration also given to the continuity of mineral assemblage information.
The ore zones exhibit spatially different classifications mainly because of
differing density of mineralogical information and variography. The reason for
the increased material tonnes between the 2019 and 2021 Kwale North Dune
Mineral Resources estimates is that the area covered by assays has increased.
The reason for the increased confidence levels in the 2021 Kwale North Dune
Mineral Resources estimate is refined variography assessments for Ore Zones 1
and 5 which indicate increased ranges in the primary and/or secondary
directions of grade continuity compared to the 2019 Kwale North Dune Mineral
Resources. The 2021 Kwale North Dune Mineral Resources estimate used a 1% HM
bottom cut because the economic cut-off grade at the nearby Kwale South Dune
deposit mine is near to this, and resource estimates for Kwale Operations have
historically been reported at this cut-off grade. Figures 4, 6 and 7 show the
distribution of the resource classifications for Ore Zones 1, 4 and 5,
respectively.
Further information specific to the 2021 Bumamani Mineral Resources estimate
The geological interpretations for the Bumamani deposit considered the data in
the drill logs, HM assay results, microscopic logging of HM sinks, detailed
mineralogy and knowledge gained from mining the Central Dune and South Dune
deposits. Three geological domains have been identified at the Bumamani
deposit. These were used and honoured during the geological modelling (Figure
8).
The uppermost zone at the Bumamani deposit, referred to as Ore Zone 1 (Figure
9), is a dark brown, predominantly fine grained, well sorted silty sand with
very little induration and is similar to the Ore Zone 1 units in the other
Kwale deposits. It averages 1.9% HM, 21% SL and 4% OS. The zone gets sandier
to the east with reduced silt content. Mineralogically it is characterised by
clean, glossy and rounded HM grains with an average VHM content of
approximately 70% VHM.
Ore Zone 4 (Figure 10) lies below Ore Zone 1, with the two zones separated by a
lateritic paleo-surface which may imply a time-gap in depositional history.
Ore Zone 4 is a fluviatile unit represented locally with poorly sorted sandy
clays and gritty sands. The Ore Zone 4 domain averages 1.8% HM, 23.6% SL and
6.4% OS. Ore Zone 4 is mineralogically similar to Ore Zone 1.
The Basement Zone at the Bumamani deposit lies beneath Ore Zone 4 and comprises
compacted clays, sandy-clays, limestone and fluvial sands. The grain sizes
range from silt to pebbles and boulders, with generally poor sorting and is
characterised by trace concentrations of HM typically with low VHM content.
For Ore Zones 1 and 4, a strong correlation between the field logs, HM sink
logs and XRF oxide chemistry and QEMSCAN mineralogy gives confidence to these
interpretations.
Drilling by Base Resources' wholly-owned subsidiary, Base Titanium Limited, of
the Bumamani deposit was completed using the RCAC method and conducted in two
campaigns in 2017 and 2018, both employing 76mm diameter, 3m long NQ drill
rods. A total of 183 holes were drilled for 2,977.5m at 1.5m sampling
intervals and generated 1,968 assayed samples. Holes were drilled 50m apart on
lines 100m apart. Samples were split using a rig mounted rotary splitter which
delivered an average of 2.7kg of dry sample per interval. Samples were dried,
weighed, and screened for material less than 45 micrometres (slimes) and +1mm
(oversize).
Approximately 100 grams of the screened sample was subjected to a HM float/sink
technique using the heavy liquid, lithium polytungstate (LST) with a specific
gravity of 2.85 grams per cubic centimetre. The resulting HM concentrate was
dried and weighed as were the other separated constituent size fractions (the
minus 45 micrometre material being calculated by difference).
Mineral assemblage analyses were conducted by Base Resources to characterise
the mineralogical and chemical characteristics of specific mineral species and
magnetic fractions. These mineral assemblage samples were subjected to
magnetic separation using a Mineral Technologies induced-roll magnetic
separator which captures mag, mid and non-mag fractions. The mid and mag
fractions were combined and, with the non-mag fraction, were subjected to XRF
analysis using a Bruker, S8 Tiger XRF.
Data from the mag and non-mag XRF analyses was processed through the Minmod
algorithm that runs approximately 100,000 iterations in assigning key chemical
species to derive a calculated mineralogy determination.
Drill hole collar and geology data was captured by industry-specific, field
logging software with on-board validation. Field and assay data were managed
in a MS Access database and subsequently migrated to a more secure SQL
database.
Standard samples were generated and certified for use in the field and
laboratory. Accuracy of HM and SL analysis was verified by using the standard
samples and monitored using control charts. Standard errors greater than three
standard deviations from the mean prompted batch re-assay. A standard
precision analysis was conducted on the key assay fields: HM, SL and OS for
both laboratory and field duplicate samples. Normal scatter and QQ plots were
prepared for HM, SL and OS for laboratory and field duplicates.
A twin drilling program was introduced for the 2018 program to quantify
short-range variability in geological character and grade intersections. A
water injection versus dry drilling assessment was included in the twin
drilling analysis. Field and laboratory duplicate, standard and twin drilling
analysis show adequate level of accuracy and precision to support resource
classifications as stated.
A topographic DTM was prepared by Base Resources based on a LIDAR survey.
Construction of the geological grade model was based on coding model cells
below open wireframe surfaces, comprising topography, geology (Ore Zones 1 and
4) and basement (Figure 8). Model cell dimensions of 50m x 50m x 1.5m in the
XYZ orientations were utilised.
Interpolation was undertaken using various sized search ellipses to populate
the model with primary grade fields (HM, SL and OS), and index fields
(hardness, induration percent, mineralogy). Inverse distance weighting to a
power of three was used for primary assay fields whilst nearest neighbour was
used to interpolate index fields. Figure 11 shows an oblique view of the model
coloured by HM grade.
A fixed bulk density of 1.7 (t/m3) was applied to the 2021 Bumamani Mineral
Resources estimate model. This bulk density was selected based on operational
experience in the Kwale Central and South Dune deposits and because no bulk
density sampling was undertaken. This is considered to be a conservative
estimate of bulk density.
The Bumamani deposit, being similar in nature to the Kwale South Dune deposit
currently being mined, is considered amenable to being mined and processed in
the same way. That is, by using the existing plant and equipment at the Kwale
Operations: hydraulic mining, spiral concentrator and mineral separation plant
with magnetic, electrostatic and further gravity separation. The only
departure from current methodology is that, for the Bumamani deposit (like for
the Kwale North Dune deposit), the fine and coarse tailings are likely to be
co-disposed together. Apart from that, there is no indication that the mining,
metallurgical and operating cost modifying factors for the Bumamani deposit
would be materially different to those derived from mining the Kwale South Dune
deposit.
The criteria used for classification was primarily the drill spacing
(predominantly 100m x 50m) and sample interval (1.5m), with consideration also
given to the continuity of mineral assemblage information. The ore zones
exhibit spatially different classifications mainly because of differing density
of mineralogical information. The 2021 Bumamani Mineral Resources estimate
used a 1% HM bottom cut because the economic cut-off grade at the nearby Kwale
South Dune deposit mine is near to this, and resource estimates for Kwale
Operations have historically been reported at this cut-off grade. Figures 9
and 10 show the distribution of the resource classifications for Ore Zones 1
and 4 respectively.
Competent Persons' Statements
2021 Kwale North Dune Mineral Resources estimate
The information in this announcement that relates to the 2021 Kwale North Dune
Mineral Resources estimate is based on, and fairly represents, information and
supporting documentation prepared by Mr. Greg Jones, who acts as a Consultant
Geologist for Base Resources and is employed by IHC Robbins. Mr. Jones is a
Fellow of The Australasian Institute of Mining and Metallurgy and has
sufficient experience that is relevant to the style of mineralisation, type of
deposits under consideration and activity which he is undertaking to qualify as
a Competent Person as defined in the JORC Code and as a Qualified Person for
the purposes of the AIM Rules for Companies. Mr. Jones has reviewed this
announcement and consents to the inclusion in this announcement of the 2021
Kwale North Dune Mineral Resources estimate and supporting information in the
form and context in which that information appears.
2021 Bumamani Mineral Resources estimate
The information in this announcement that relates to the 2021 Bumamani Mineral
Resources estimate is based on, and fairly represents, information and
supporting documentation prepared by Mr. Scott Carruthers. Mr. Carruthers is a
Member of The Australasian Institute of Mining and Metallurgy. Mr. Carruthers
is employed by Base Resources, holds equity securities in Base Resources, and
is entitled to participate in Base Resources' long-term incentive plan and
receive equity securities under that plan. Details about that plan are
included in Base Resources' 2020 Annual Report. Mr. Carruthers has sufficient
experience that is relevant to the style of mineralisation, type of deposits
under consideration and activity which he is undertaking to qualify as a
Competent Person as defined in the JORC Code and as a Qualified Person for the
purposes of the AIM Rules for Companies. Mr. Carruthers has reviewed this
announcement and consents to the inclusion in this announcement of the 2021
Bumamani Mineral Resources estimate and supporting information in the form and
context in which that information appears.
Forward Looking Statements
Certain statements in or in connection with this announcement contain or
comprise forward looking statements.
By their nature, forward looking statements involve risk and uncertainty
because they relate to events and depend on circumstances that will occur in
the future and may be outside Base Resources' control. Accordingly, results
could differ materially from those set out in the forward-looking statements as
a result of, among other factors, changes in economic and market conditions,
success of business and operating initiatives, changes in the regulatory
environment and other government actions, fluctuations in product prices and
exchange rates and business and operational risk management. Subject to any
continuing obligations under applicable law or relevant stock exchange listing
rules, Base Resources undertakes no obligation to update publicly or release
any revisions to these forward-looking statements to reflect events or
circumstances after the date of this announcement or to reflect the occurrence
of unanticipated events.
No representation or warranty, express or implied, is made as to the fairness,
accuracy or completeness of the information contained in this announcement (or
any associated presentation, information or matters). To the maximum extent
permitted by law, Base Resources and its related bodies corporate and
affiliates, and their respective directors, officers, employees, agents and
advisers, disclaim any liability (including, without limitation, any liability
arising from fault, negligence or negligent misstatement) for any direct or
indirect loss or damage arising from any use or reliance on this announcement
or its contents, including any error or omission from, or otherwise in
connection with, it.
Nothing in this announcement constitutes investment, legal or other advice.
You must not act on the basis of any matter contained in this announcement but
must make your own independent investigation and assessment of Base Resources
and obtain any professional advice you require before making any investment
decision based on your investment objectives and financial circumstances. This
announcement does not constitute an offer, invitation, solicitation, advice or
recommendation with respect to the issue, purchase or sale of any security in
any jurisdiction.
Appendix 1 - 2021 Kwale North Dune Mineral Resources estimate
JORC Code, 2012 Edition
Section 1 Sampling Techniques and Data
(Criteria in this section apply to all succeeding sections.)
Criteria Explanation Comment
Sampling Nature and quality of sampling (e.g., Reverse circulation aircore drilling
techniques cut channels, random chips, or was used to collect downhole samples
specific specialised industry for the project.
standard measurement tools
appropriate to the minerals under Of the 745 drill holes used for this
investigation, such as down hole resource update, 21 of them (drilled
gamma sondes, or handheld XRF between 2010 - mid 2012) utilised 3m
instruments, etc). These examples sample intervals. The remaining 724
should not be taken as limiting the drill holes used 1.5m sample
broad meaning of sampling. intervals from mid-2012 to 2019
using an on-board rotary splitter
Include reference to measures taken mounted beneath the rig cyclone.
to ensure sample representivity and
the appropriate calibration of any Sample gates were set to collect 25%
measurement tools or systems used. of the splitter cycle, which
delivered about 2.5 - 3.5kg of
Aspects of the determination of sample per interval on average.
mineralisation that are Material to
the Public Report. In cases where Duplicate samples were collected at
'industry standard' work has been the splitter for every 20th sample
done this would be relatively simple simultaneously with the original
(e.g., 'reverse circulation drilling sample.
was used to obtain 1 m samples from
which 3 kg was pulverised to produce A representative grab sample from
a 30 g charge for fire assay'). In the sample bags was routinely washed
other cases, more explanation may be and panned for a visual HM content
required, such as where there is estimate.
coarse gold that has inherent
sampling problems. Unusual
commodities or mineralisation types
(e.g., submarine nodules) may warrant
disclosure of detailed information.
Drilling Drill type (e.g., core, reverse 122 holes in the 2010, 2012/2013
techniques circulation, open-hole hammer, rotary campaigns were drilled with a RCAC
air blast, auger, Bangka, sonic, etc) Wallis Mantis 75 drill rig using NQ
and details (e.g., core diameter, drill tooling of about 76mm in
triple or standard tube, depth of diameter.
diamond tails, face-sampling bit or
other type, whether core is oriented 567 holes in the 2018 campaign and
and if so, by what method, etc). the 56 holes in the 2019 campaign
were drilled with a more modernised
Mantis 80 drill rig, also using NQ
drill bits.
For the 2010 and 2012/13 campaigns,
the mast was oriented vertically (90
º) by sight. For the 2018/19
drilling campaign, the rig mast was
orientated vertically by spirit
level prior to drilling to adhere to
best practice for geological
boundary delineation.
Drilling was recorded in geological
logs as either dry or water
injected, depending on ground
conditions. Water injection was
employed to assist with penetration
through clays/rock and maintain
sample quality and delivery.
Drill sample Method of recording and assessing Sample condition was logged at the
recovery core and chip sample recoveries and rig as either good, moderate or
results assessed. poor, with good meaning not
contaminated and appropriate sample
Measures taken to maximise sample size (recovery), moderate meaning
recovery and ensure representative not contaminated, but sample over or
nature of the samples. under sized, and poor meaning
contaminated or grossly over/
Whether a relationship exists between undersized.
sample recovery and grade and whether
sample bias may have occurred due to Slightly damp ground conditions with
preferential loss/gain of fine/coarse approximately 36% silt/clay meant
material. that best sample quality was found
to be achieved via slow penetration
with water injection to aid in the
sample recovery.
No relationship is believed to exist
between grade and sample recovery.
No bias is also believed to occur
due to loss of fine material.
Logging Whether core and chip samples have Field logging was recorded for all
been geologically and geotechnically 16,257 fixed, down-hole intervals
logged to a level of detail to and was conducted as drilling and
support appropriate Mineral Resource sampling proceeded. Logging was
estimation, mining studies and based on a representative grab
metallurgical studies. sample that was panned for heavy
mineral estimation and host material
Whether logging is qualitative or observations.
quantitative in nature. Core (or
costean, channel, etc) photography. Logging codes were designed to
capture observations on lithology,
The total length and percentage of colour, grainsize, induration and
the relevant intersections logged. estimated mineralisation. Any
relevant comments e.g., water table,
gangue HM components and
stratigraphic markers were included
to aid in the subsequent geological
modelling.
A qualitative estimate of how
representative a sample was of the
drilled interval was recorded by
Base Titanium Limited (BTL) field
geologists whilst logging. This
sample condition field records
whether the hole was drilled with
injected water or dry and sample
size (and the influence of
contamination or sample loss)
directs the quality assessment of
each sample.
Heavy mineral sinks from assayed
samples were logged routinely under
a reflected-light, stereoscopic
microscope. This work was carried
out to capture information relating
to VHM content, mineralogy, HM
grainsize and quality.
Sub-sampling If core, whether cut or sawn and Rotary split at the sampling cyclone
techniques whether quarter, half or all core on the rig. Approximately 25% of
and sample taken. the original sample retained.
preparation Duplicate samples were collected at
If non-core, whether riffled, tube every 20th sample. The drill rods
sampled, rotary split, etc and and cyclone were routinely cleaned
whether sampled wet or dry. between holes using pressurised
water to avoid inter-hole
For all sample types, the nature, contamination. The sample size is
quality and appropriateness of the considered appropriate for the grain
sample preparation technique. size of the material because the
grade of HM is measured in per cent,
Quality control procedures adopted and a 2.5-5kg sample contains in
for all sub-sampling stages to excess of 50 million grains of sand.
maximise representivity of samples.
The sample preparation flow sheet
Measures taken to ensure that the departed from standard mineral sand
sampling is representative of the practices in one respect; the
in-situ material collected, including samples were not oven dried prior to
for instance results for field de-sliming, to prevent clay minerals
duplicate/second-half sampling. being baked onto the HM grains
(because the HM fractions were to be
Whether sample sizes are appropriate used in further mineralogical test
to the grain size of the material work). Instead, a separate sample
being sampled. was split and dried to determine
moisture content, which was
accounted for mathematically.
Pre-soaking of the sample Sodium
(Tetra) Pyrophosphate (TSPP)
dispersant solution ensured a more
efficient de-sliming process and to
avoid potentially under-reporting
slimes content.
Quality of The nature, quality and The assay process employed included
assay data appropriateness of the assaying and a Sample Preparation stage,
and laboratory procedures used and completed by BTL staff, followed by
laboratory whether the technique is considered a heavy liquid separation (using
tests partial or total. lithium polytungstate: SG = 2.85g/
cm3), completed at Kwale Operations'
For geophysical tools, spectrometers, site laboratory.
handheld XRF instruments, etc, the
parameters used in determining the Improvements to the sample
analysis including instrument make preparation stage were made to
and model, reading times, ensure industry best practice and to
calibrations factors applied and deliver a high degree of confidence
their derivation, etc. in the results. These included the
following:
Nature of quality control procedures
adopted (e.g., standards, blanks, * A formalised process flow was
duplicates, external laboratory generated, posted in all sample
checks) and whether acceptable levels preparation areas and used to
of accuracy (i.e., lack of bias) and train and monitor sample
precision have been established. preparation staff
* Regular monitoring was completed
by BTL senior staff
* Field samples were left in their
bags for initial air-drying to
avoid sample loss
* TSPP was introduced to decrease
attrition time and improve
slimes recovery.A range of
attrition times (with 5% TSPP)
were trialled and plotted
against slimes recovery figures
to determine optimum attrition
time (15 minutes)
* Staff were trained to use paint
brushes and water spray rather
than manipulate sample through
slimes screen by hand to remove
the potential for screen damage
* A calibration schedule was
introduced for scales used in
the sample preparation stage
* The introduction of ruggedized
computers allowed the capture of
sample preparation data
digitally at inception.This
greatly reduced the instance of
scribe and data entry errors
* Slimes screen number recorded to
isolate batches should re-assay
be required due to poor
adherence to procedure or to
identify screen damage
* Various quality control samples
were submitted routinely to
assure assay quality. A total
of 809 duplicate field samples,
809 lab duplicate sample
preparation samples, 279 field
certified standard samples, and
an unspecified number of
internal laboratory standards,
repeats and blanks have been
assayed at Kwale Operations'
site laboratory.
Verification The verification of significant The Kwale North Dune deposit is a
of sampling intersections by either independent moderate to low HM grade,
and assaying or alternative company personnel. dunal-style accumulation that does
not carry excessive mineralisation
The use of twinned holes. or suffer from 'nugget' effects,
typical of other commodities.
Documentation of primary data, data
entry procedures, data verification, No external audit validation was
data storage (physical and completed for the HM analyses
electronic) protocols. included in the 2021 Kwale North
Discuss any adjustment to assay data. Dune Mineral Resources estimate.
This is not considered material
given the adequate performance of
results from extensive QA/QC
verification and on account of low
HM grade variance and deposit
homogeneity.
A twin drill hole procedure was
introduced for the 2018/19 program
at a recommended rate of 5% of the
total number of holes. These twins
were used to quantify short-range
variability in geological character
and grade intersections and ideally
should be placed throughout the
deposit.
A total of 41 twin drill holes were
completed during the 2018/19 Kwale
North Dune drilling program, which
represents about 5.7% of the total
program.
The spatially well-represented twin
hole paired data shows very good
correlation considered material to
the integrity/quality of the
resource data.
Location of Accuracy and quality of surveys used Proposed drill holes were sited on
data points to locate drill holes (collar and the ground using hand-held GPS.
down-hole surveys), trenches, mine After drilling, surveyors recorded
workings and other locations used in collar positions via DGPS RTK unit
Mineral Resource estimation. registered to local base stations.
The accuracy of the DGPS unit is
Specification of the grid system stated at 0.02m in the X, Y and Z
used. axes.
Quality and adequacy of topographic The survey Geodetic datum utilised
control. was UTM Arc 1960, used in E. Africa.
Arc 1960 references the Clark 1880
(RGS) ellipsoid and the Greenwich
prime meridian. All survey data
used in the 2021 Kwale North Mineral
Resources estimate dataset has
undergone a transformation to the
local mine grid from the standard
UTM Zone 37S (Arc 1960). The local
Grid was rotated 42.5o, which aligns
the average strike of the deposit
with local North and is useful for
both grade interpolation and mining
reference during production.
All drill collars were projected to
the local LIDAR survey, digital
terrain model, captured over the
resource area in 2018/19 at a 2x2m
grid spacing. This was performed
prior to interpretation and model
construction to eliminate any
elevation disparities for the block
model construction.
Data spacing Data spacing for reporting of The drill data spacing for the 2018/
and Exploration Results. 19 Kwale North Resource drilling was
distribution nominally 100m X, 100m Y and 1.5m
Whether the data spacing, and Z. Variations from this spacing
distribution is sufficient to resulted from terrain/traverse
establish the degree of geological difficulties and ground access.
and grade continuity appropriate for
the Mineral Resource and Ore Reserve A sample spacing of 3m, with
estimation procedure(s) and occasional 1.5m intervals at
classifications applied. geological contacts, was employed in
the 2012/2013 drilling campaign by
Whether sample compositing has been BTL.
applied.
A 3m, down-hole block size was
applied to model construction and
for consistency in the interpolation
processes.
This spacing and distribution is
considered sufficient to establish
the degree of geological and
mineralisation continuity
appropriate for the resource
estimation procedures and
classifications applied.
No sample compositing has been
applied for HM, slimes and oversize
in the interpolation processes.
Orientation Whether the orientation of sampling With the geological setting being a
of data in achieves unbiased sampling of layered dunal/fluviatile sequence,
relation to possible structures and the extent to the orientation of the deposit
geological which this is known, considering the mineralisation in general is
structure deposit type. sub-horizontal. All drill holes were
orientated vertically to penetrate
If the relationship between the the sub-horizontal mineralisation
drilling orientation and the orthogonally.
orientation of key mineralised
structures is considered to have Hole centres were spaced nominally
introduced a sampling bias, this at 100m. This cross-profiles the
should be assessed and reported if dune so that variation can be
material. determined. Down hole intervals were
nominated as 1.5m. This provides
adequate sampling resolution to
capture the distribution and
variability of geology units and
mineralisation encountered
vertically down hole.
The orientation of the drilling is
considered appropriate for testing
the horizontal and vertical extent
of mineralisation without bias.
Sample The measures taken to ensure sample Sample residues from the prep stage
security security. were transferred to pallets and
stored in a locked shed beside the
warehouse at Kwale Operations.
Residues from the Kwale Operations
site laboratory were placed in
labelled bags and stored in numbered
boxes. Boxes were placed into a
locked container beside the
laboratory.
Sample tables are housed on a
secure, network-hosted SQL
database. Administration privileges
are limited to two BTL staff:
Exploration Superintendent and the
Business Applications Administrator.
Data is backed up every 12 hours and
stored in perpetuity on a secure,
site backup server.
Audits or The results of any audits or reviews In-house reviews were undertaken by
reviews of sampling techniques and data. the Base Resources' Resources
Manager, Mr. Scott Carruthers who is
a Competent Person under the JORC
Code.
Section 2 Reporting of Exploration Results
(Criteria listed in the preceding section also apply to this section.)
Criteria Explanation Comment
Mineral Type, reference name/number, The Kwale North Dune is situated on a
tenement and location and ownership Prospecting License (PL) 100% owned by Base
land tenure including agreements or Titanium Limited - PL/2018/0119 located in
status material issues with third Kwale County, Kenya. Base Titanium Limited
parties such as joint is a wholly owned subsidiary of Australian
ventures, partnerships, and UK-listed resources company, Base
overriding royalties, native Resources Limited.
title interests, historical
sites, wilderness or national The 88.7 km2 Prospecting License was granted
park and environmental on the 26th of May 2018 for a three-year
settings. term ending 25th May 2021.
The security of the tenure The PL is in good standing with the Kenya
held at the time of reporting Ministry of Petroleum & Mining at the time
along with any known of reporting, with all statutory reporting
impediments to obtaining a and payments up to date.
licence to operate in the
area. Local landowners generally supportive of
exploration activities with over 90% of
planned holes drilled.
The existing Special Mining Lease 23 lies
within the Prospecting license area and
covers the Kwale Central Dune deposit and
some of the Kwale South Dune deposit but
does not include the Kwale North Dune
deposit. The Kenya Mining Act 2016 includes
provision for the amendment of an existing
SML and for the conversion of an existing PL
to SML.
Exploration Acknowledgment and appraisal In 1996, Tiomin carried out reconnaissance
done by other of exploration by other surface and hand-auger sampling.
parties parties.
Following the encouraging results obtained,
mud-rotary drilling was undertaken in 1997
and 37 holes for a total of 1,824m was
achieved for the North dune, at 3m sampling
intervals.
Prior to acquisition of the Kwale Project by
Base Resources, Tiomin prepared and
published a North Dune Mineral Resources
estimate of 116 Mt @ 2.1% HM using a 0.5% HM
cut-off grade.
The current resource model omits the Tiomin
data. This followed a twin drilling analysis
of the Tiomin Mud Rotary holes with Base
Resources' RCAC to determine relevance of
historical data to the Kwale South Dune
Mineral Resources estimate in 2016. A total
of 18 twin-hole pairs from a geographically
dispersed area within the South Dune were
included for analysis. A very poor
correlation in HM values between the two
methods (R2 = 0.1522) resulted from the
study. It is assumed that the poor
correlation would extend to the North Dune.
This is expected, given the open-hole method
of drilling employed by Tiomin and supports
the decision to exclude Tiomin data from the
current interpolation.
Geology Deposit type, geological The North Dune is part of the extensive
setting and style of Kwale Dune systems comprising of reddish,
mineralisation. windblown Magarini sand formations that
overlie a sequence of mineralised clay-rich
fluviatile units, which in turn overlie a
Mesozoic sandstone Base, known as the
Mazeras formation.
These three units are separated by lateritic
paleo-surfaces which signify a time-gap
between the geological formations.
The Mazeras Sandstone, derived from the
disintegration of the Mozambique Belt
metamorphic rocks, has likely provided the
supply of heavy minerals to the Magarini
sand dunes and the fluviatile formations.
Exploration of the Kenyan coastline is yet
to be successful in terms of mineralised
paleo-strandlines related to fossil marine
terraces, as these are likely buried beneath
recent barren fluvial overburden or were
just not developed owing to reduced energy
levels from a fringing coral reef that has
acted as a barrier to effective winnowing
and reworking of HM deposits.
Drill hole A summary of all information Drilling by year (max, min and average
Information material to the understanding depths) used for the resource model build
of the exploration results are as follows:
including a tabulation of the
following information for all * 2010
Material drill holes: + 11 drill holes (depth: max 72m, min
24m, avg 56m).
+ Total 582m drilled.
If the exclusion of this * 2012
information is justified on + 31 drill holes (depth: max 75m, min
the basis that the 18m, avg 60m).
information is not Material + Total 1,681.5m drilled.
and this exclusion does not * 2013
detract from the + 80 drill holes (depth: max 75m, min
understanding of the report, 27m, avg 55m).
the Competent Person should + Total 3,792m drilled.
clearly explain why this is * 2018
the case. + 567 drill holes (depth: max 117m,
min 6m, avg 45 m).
+ Total 20,477m drilled.
* 2019
+ 56 drill holes (depth: max 30m, min
9m, avg 30m).
+ Total 897m drilled.
See drill hole location plan, Figure 4.
All drill holes drilled vertically.
Exploration results are not being reported
at this time.
Data In reporting Exploration Exploration results are not being reported
aggregation Results, weighting averaging at this time.
methods techniques, maximum and/or
minimum grade truncations No equivalent values were used.
(e.g., cutting of high
grades) and cut-off grades No aggregation of short length samples used
are usually Material and as samples were consistently 3m and 1.5m
should be stated. intervals.
Where aggregate intercepts
incorporate short lengths of
high-grade results and longer
lengths of low-grade results,
the procedure used for such
aggregation should be stated
and some typical examples of
such aggregations should be
shown in detail.
The assumptions used for any
reporting of metal equivalent
values should be clearly
stated.
Relationship These relationships are The deposit sequences are sub-horizontal,
between particularly important in the and the vertically inclined holes are a fair
mineralisation reporting of Exploration representation of true thickness.
widths and Results.
intercept
lengths If the geometry of the
mineralisation with respect
to the drill hole angle is
known, its nature should be
reported.
If it is not known and only
the down hole lengths are
reported, there should be a
clear statement to this
effect (e.g., 'down hole
length, true width not
known').
Diagrams Appropriate maps and sections See figures 3-7.
(with scales) and tabulations
of intercepts should be
included for any significant
discovery being reported
These should include, but not
be limited to a plan view of
drill hole collar locations
and appropriate sectional
views.
Balanced Where comprehensive reporting Exploration results are not being reported
reporting of all Exploration Results is at this time.
not practicable,
representative reporting of
both low and high grades and/
or widths should be practiced
to avoid misleading reporting
of Exploration Results.
Other Other exploration data, if The proprietary Minmod mineralogy technique,
substantive meaningful and material, developed and employed by Base Resources,
exploration should be reported including comprises an XRF analysis of the magnetic
data (but not limited to): and non-magnetic fractions of each composite
geological observations; or sample, the results from which are then
geophysical survey results; back-calculated to determine in-ground
geochemical survey results; mineralogy. Minmod represents an
bulk samples - size and improvement on the previous method (Geomod)
method of treatment; that was not as effective at determining
metallurgical test results; accessory minerals in the Kwale assemblage.
bulk density, groundwater, Minmod has been validated by external
geotechnical and rock quantitative analysis (QEMSCAN and SEM EDX)
characteristics; potential and is considered sufficiently certified to
deleterious or contaminating support quoted resource confidence in this
substances. report.
Further work The nature and scale of Additional 100 x 100m aircore drilling to
planned further work (e.g., in-fill gaps and extend mineralisation in
tests for lateral extensions the open NW part of the deposit.
or depth extensions or
large-scale step-out Recommended 50 x 50m aircore drilling across
drilling). strike primarily to improve across strike
variography for Ore 4.
Diagrams clearly highlighting
the areas of possible Generation of further Ore Zone 5 QEMSCAN
extensions, including the composites for a more confident
main geological mineralogical modelling.
interpretations and future
drilling areas, provided this Detailed tests to establish accurate bulk
information is not densities.
commercially sensitive.
Section 3 Estimation and Reporting of Mineral Resources
(Criteria listed in section 1, and where relevant in section 2, also apply to
this section.)
Criteria Explanation Comment
Database Measures taken to ensure that Field data was captured in LogChief logging
integrity data has not been corrupted application and automatically validated
by, for example, through reference to pre-set library table
transcription or keying configurations.
errors, between its initial
collection and its use for Typing or logging code errors, duplication
Mineral Resource estimation of key identifiers (e.g., HOLE_ID, SAMP_ID)
purposes. and conflicts in related tables (e.g.,
down-hole depth) are quarantined by the
Data validation procedures software and require resolving immediately
used. before logging can proceed.
The SQL Database also has identical
automated validation features. Data import
is unsuccessful until these data issues are
resolved.
Field logging and survey data from the SQL
database were imported into Datamine
Discover (MapInfo) for sectional
interpretation.
Validation steps included a visual
interrogation of collar versus geology
depths, a review of hole locations against
the drilling plan and a check for missing or
duplicated logged fields and outliers. Any
spurious or questionable entries were
resolved by the supervising Geologist.
At the completion of each hole, an entry was
made to the hand-written drilling diary. The
diary recorded the hole name, date, depth,
number of samples, time of start and finish,
a description of the location of the hole in
relation to the last hole and other things.
Such a diary provides valuable evidence if
there is an error in hole naming or
surveying.
A geologist was employed to manage digital
data capture at the sample preparation
laboratory to reduce the potential for data
entry error by unskilled labourers. A
number of validation checks were made of
sample preparation data to ensure accurate
data entry and application of correct
procedure by BTL staff. This included:
* comparison of pre- versus post-oven
weights
* comparison of split weight versus
de-slimed weight
* comparison of split weight versus field
sample weight
* all sample preparation data were sorted
by each individual field and outliers
investigated
Assay results were delivered via email in 45
sample batches from Kwale Operations' site
laboratory. These were in the form of CSV
text files and imported by batch number
directly into the SQL database tables where
pre-set algorithms converted weights to
percentages and removed the moisture
content. The calculated assay results were
then checked manually for missing records
and out of range or unrealistic values.
Site visits Comment on any site visits Base Resources' Resources Manager Scott
undertaken by the Competent Carruthers made one site visit to review the
Person and the outcome of SQL database and the geological
those visits. interpretations. The Competent Person is
satisfied with the integrity of the database
If no site visits have been as well as the delineation of the geological
undertaken indicate why this boundaries.
is the case.
Geological Confidence in (or conversely, The geological interpretation was undertaken
interpretation the uncertainty of) the by the BTL Exploration Superintendent using
geological interpretation of field logs and observations, assays, HM
the mineral deposit. sachet logs, XRF oxide chemistry and
mineralogy data. The oversize grades were
Nature of the data used and particularly useful in determining the
of any assumptions made. lateritic paleo-surfaces between the
geological zones.
The effect, if any, of
alternative interpretations The data spacing for the project is
on Mineral Resource considered sufficient for grade and
estimation. mineralogical continuity.
The use of geology in guiding Four mineralised geological zones and a
and controlling Mineral basement zone were identified and are used
Resource estimation. as constraints in the Mineral Resources
estimation.
The factors affecting
continuity both of grade and The uppermost zone at Kwale North, referred
geology. to as Ore Zone 1, is a dark brown,
predominantly fine grained, well sorted
silty sand with very little induration. It
is also characterised by a clean, high value
heavy mineral assemblage.
Ore Zone 4 lies below Ore Zone 1 with a
clear lateritic boundary observed in the
field with slightly difficult bit
penetration, and in HM sink logs, exhibiting
elevated iron oxides. Ore Zone 4 is lower
in valuable heavy mineral content, often
dominated by iron oxides and Al2SiO4
polymorphs (kyanite, andalusite and
sillimanite). It is considered a fluvial
deposit based on the difficulty of wash and
the poor grain sorting.
Ore Zone 5 lies below Ore Zone 4 and is
separated from that zone by a lateritic
paleo-surface. It is unique mineralogically
due to an increased amount of almandine
garnet that reports to the mag fraction,
significantly increasing the magnesium,
manganese, aluminium and silicon in the
oxide chemistry, and this is also reflected
in QEMSCAN mineralogy.
For Ore Zones 1, 4 and 5, a strong
correlation between the field logs, HM sink
logs and XRF oxide chemistry and QEMSCAN
mineralogy gives confidence to these
interpretations.
The grade and mineralogy continuity is
abruptly truncated at the western edge by an
interpreted normal fault that pushed
basement material to the surface with
resultant low grades and trash HM.
Dimensions The extent and variability of The 2021 Kwale North Dune Mineral Resources
the Mineral Resource estimate is approximately 6,300m along
expressed as length (along strike and about 1,200m across strike on
strike or otherwise), plan average.
width, and depth below
surface to the upper and The average thickness of Ore 1, Ore 4 and
lower limits of the Mineral Ore 5 are approximately 10m, 7m and 5m
Resource. respectively.
Estimation and The nature and The 2021 Kwale North Dune Mineral Resources
modelling appropriateness of the estimation was undertaken using Datamine
techniques estimation technique(s) Studio RM software.
applied and key assumptions,
including treatment of Inverse Distance Weighting to the power of
extreme grade values, three was used to interpolate assay grades
domaining, interpolation (HM, Slimes, Oversize) from the drill hole
parameters and maximum file.
distance of extrapolation
from data points. If a Nearest Neighbour was used to interpolate
computer assisted estimation the composite ID and mineralogy data.
method was chosen include a
description of computer This is an update to the previous (and
software and parameters used. maiden JORC 2012) 2019 Kwale North Dune
Mineral Resources estimate, which was 171 Mt
The availability of check @ 1.5% HM using a 1.0% cut-off grade. No
estimates, previous estimates mining has been undertaken.
and/or mine production
records and whether the No assumptions have been made as to the
Mineral Resource estimate recovery of by-products.
takes appropriate account of
such data. The parent cell size used in the grade
interpolation (50m x 50m) was half the
The assumptions made average drill hole spacing on the X and Y
regarding recovery of axes, which was 100m x 100m. The vertical
by-products. thickness of the cell was the nominal
average drill sample interval i.e., 1.5m.
Estimation of deleterious
elements or other non-grade No assumptions were made behind modelling of
variables of economic selected mining units.
significance (e.g., sulphur
for acid mine drainage No assumptions made about correlation behind
characterisation). variables.
In the case of block model Validation was undertaken by swathe plots,
interpolation, the block size population distribution analysis and visual
in relation to the average inspection.
sample spacing and the search
employed. The geological zones were used to control
the resource estimate by constraining grade
Any assumptions behind interpolations and reporting.
modelling of selective mining
units.
Any assumptions about
correlation between
variables.
Description of how the
geological interpretation was
used to control the resource
estimates.
Discussion of basis for using
or not using grade cutting or
capping.
The process of validation,
the checking process used,
the comparison of model data
to drill hole data, and use
of reconciliation data if
available.
Moisture Whether the tonnages are The Mineral Resources estimate is on a dry
estimated on a dry basis or tonnes basis.
with natural moisture, and
the method of determination
of the moisture content.
Cut-off The basis of the adopted The economic cut-off of Kwale Operations is
parameters cut-off grade(s) or quality between 1% and 1.5% HM, and historically
parameters applied. Kwale Operations Mineral Resources estimate
reporting focuses on a 1% HM cut-off grade.
Mining factors Assumptions made regarding It is assumed that the hydraulic mining
or assumptions possible mining methods, method used at the neighbouring Kwale
minimum mining dimensions and Operations would be used. The high slime
internal (or, if applicable, content and generally low levels of
external) mining dilution. It induration in the North Dune deposit provide
is always necessary as part support for this mining method. This mining
of the process of determining method is being re-assessed as part of the
reasonable prospects for Kwale North Dune PFS.
eventual economic extraction
to consider potential mining
methods, but the assumptions
made regarding mining methods
and parameters when
estimating Mineral Resources
may not always be rigorous.
Where this is the case, this
should be reported with an
explanation of the basis of
the mining assumptions made.
Metallurgical The basis for assumptions or The existing concentrator, modified to
factors or predictions regarding accommodate the increased slimes, and
assumptions metallurgical amenability. It mineral separation plant at Kwale Operations
is always necessary as part are assumed capable of processing the
of the process of determining material with recoveries expected to be
reasonable prospects for aligned with present production.
eventual economic extraction
to consider potential
metallurgical methods, but
the assumptions regarding
metallurgical treatment
processes and parameters made
when reporting Mineral
Resources may not always be
rigorous. Where this is the
case, this should be reported
with an explanation of the
basis of the metallurgical
assumptions made.
Environmental Assumptions made regarding Tailing disposal is likely to utilise
factors or possible waste and process co-disposal of fine and coarse tails
assumptions residue disposal options. It together, initially into the Kwale Central
is always necessary as part pit void. Once space is available, tailings
of the process of determining would be co-disposed into the Kwale North
reasonable prospects for pit void.
eventual economic extraction
to consider the potential
environmental impacts of the
mining and processing
operation. While at this
stage the determination of
potential environmental
impacts, particularly for a
greenfields project, may not
always be well advanced, the
status of early consideration
of these potential
environmental impacts should
be reported. Where these
aspects have not been
considered this should be
reported with an explanation
of the environmental
assumptions made.
Bulk density Whether assumed or A fixed dry bulk density of 1.7 (t/m3) was
determined. If assumed, the assumed for the Mineral Resource estimation,
basis for the assumptions. If based on operational experience of mining
determined, the method used, the Kwale Central Dune and South Dune
whether wet or dry, the deposits.
frequency of the
measurements, the nature,
size and representativeness
of the samples.
The bulk density for bulk
material must have been
measured by methods that
adequately account for void
spaces (vugs, porosity, etc),
moisture and differences
between rock and alteration
zones within the deposit.
Discuss assumptions for bulk
density estimates used in the
evaluation process of the
different materials.
Classification The basis for the The Mineral Resource classification for the
classification of the Mineral Kwale North deposit was based on drill hole
Resources into varying spacing, sample interval and the
confidence categories. distribution and influence of composite
mineralogical samples.
Whether appropriate account
has been taken of all The classification of the Measured,
relevant factors (i.e., Indicated, and Inferred Mineral Resources
relative confidence in was supported by the uniform grid spacing of
tonnage/grade estimations, drilling, uncomplicated and consistent
reliability of input data, geology, relatively good continuity of
confidence in continuity of mineralisation particularly along strike
geology and metal values, (and supported by the domain controlled
quality, quantity and variography), confidence in the down hole
distribution of the data). drilling data and supporting criteria as
noted above.
Whether the result
appropriately reflects the As Competent Person, IHC Robbins Geological
Competent Person's view of Services Manager, Greg Jones, considers that
the deposit. the result appropriately reflects a
reasonable view of the deposit
categorisation.
Audits or The results of any audits or Peer review was undertaken by Scott
reviews. reviews of Mineral Resource Carruthers, Base Resources' Resources
estimates. Manager, with focus on the process and
output of the geology interpretation,
database integrity, whether wireframes
reflect the geological interpretation, and
model vs. drill hole grades. Mr. Carruthers
was satisfied with these facets.
Discussion of Where appropriate a statement Variography was undertaken to determine the
relative of the relative accuracy and drill hole support of the selected JORC
accuracy/ confidence level in the classification.
confidence Mineral Resource estimate
using an approach or Validation of the model vs drill hole grades
procedure deemed appropriate by direct observation and comparison of the
by the Competent Person. For results on screen.
example, the application of
statistical or geostatistical The resource statement is a global estimate
procedures to quantify the for the entire known extent of the Kwale
relative accuracy of the North deposit within the tenement area.
resource within stated
confidence limits, or, if
such an approach is not
deemed appropriate, a
qualitative discussion of the
factors that could affect the
relative accuracy and
confidence of the estimate.
The statement should specify
whether it relates to global
or local estimates, and, if
local, state the relevant
tonnages, which should be
relevant to technical and
economic evaluation.
Documentation should include
assumptions made and the
procedures used.
These statements of relative
accuracy and confidence of
the estimate should be
compared with production
data, where available.
Appendix 2 - 2021 Bumamani Mineral Resources estimate
JORC Code, 2012 Edition
Section 1 Sampling Techniques and Data
(Criteria in this section apply to all succeeding sections.)
Criteria JORC Code explanation Commentary
Sampling Nature and quality of Reverse circulation aircore drilling was used
techniques sampling (e.g., cut channels, to collect downhole samples for the project.
random chips, or specific
specialised industry standard Sample sub-splits were collected at 1.5m
measurement tools appropriate down-hole intervals for holes drilled, using
to the minerals under an on-board rotary splitter mounted beneath
investigation, such as down the rig cyclone.
hole gamma sondes, or
handheld XRF instruments, Sample gates were set to collect
etc). These examples should approximately 25% of the splitter cycle,
not be taken as limiting the which delivered about 2.7kg of sample per
broad meaning of sampling. interval on average.
Include reference to measures Rig duplicate samples were collected at the
taken to ensure sample splitter for every 20th sample simultaneously
representivity and the with the original sample.
appropriate calibration of
any measurement tools or A representative grab sample from the sample
systems used. bags was routinely washed and panned for
lithological logging and HM grade estimate.
Aspects of the determination
of mineralisation that are
Material to the Public
Report.
In cases where 'industry
standard' work has been done
this would be relatively
simple (e.g., 'reverse
circulation drilling was used
to obtain 1 m samples from
which 3 kg was pulverised to
produce a 30 g charge for
fire assay'). In other cases,
more explanation may be
required, such as where there
is coarse gold that has
inherent sampling problems.
Unusual commodities or
mineralisation types (e.g.,
submarine nodules) may
warrant disclosure of
detailed information.
Drilling Drill type (e.g., core, 40 holes in the 2017 campaign were drilled
techniques reverse circulation, with a RCAC Wallis Mantis 80 drill rig using
open-hole hammer, rotary air NQ drill tooling of about 76mm in diameter
blast, auger, Bangka, sonic, and a drilling capability of 100m.
etc) and details (e.g., core
diameter, triple or standard 143 holes in the 2018 campaign were similarly
tube, depth of diamond tails, drilled with a Mantis 80 drill rig, also
face-sampling bit or other using NQ drill bits.
type, whether core is
oriented and if so, by what For both drilling campaigns, the rig mast was
method, etc). orientated vertically by spirit level prior
to drilling to adhere to best practice for
geological boundary delineation.
Drilling was recorded in geological logs as
either dry or water injected, depending on
ground conditions. Water injection was
employed to assist with penetration through
clays/rock and maintain sample quality and
delivery.
Drill sample Method of recording and Sample condition was logged at the rig as
recovery assessing core and chip either good, moderate or poor, with good
sample recoveries and results meaning not contaminated and appropriate
assessed. sample size (recovery), moderate meaning not
contaminated, but sample over or under sized
Measures taken to maximise and poor meaning contaminated or grossly over
sample recovery and ensure /undersized.
representative nature of the
samples. Slightly damp ground conditions with
approximately 20% silt/clay meant that best
Whether a relationship exists sample quality was found to be achieved via
between sample recovery and slow penetration with water injection to aid
grade and whether sample bias in the sample recovery.
may have occurred due to
preferential loss/gain of No relationship is believed to exist between
fine/coarse material. grade and sample recovery. No bias is also
believed to occur due to loss of fine
material.
Logging Whether core and chip samples Field logging was recorded for all 1,968
have been geologically and fixed, down-hole intervals and was conducted
geotechnically logged to a as drilling and sampling proceeded. Logging
level of detail to support was based on a representative grab sample
appropriate Mineral Resource that was panned for heavy mineral estimation
estimation, mining studies and host material observations.
and metallurgical studies.
Logging codes were designed to capture
Whether logging is observations on lithology, colour, grainsize,
qualitative or quantitative induration and estimated mineralisation. Any
in nature. Core (or costean, relevant comments e.g., water table, gangue
channel, etc) photography. HM components and stratigraphic markers were
included to aid in the subsequent geological
The total length and modelling.
percentage of the relevant
intersections logged.
Sub-sampling If core, whether cut or sawn Rotary split at the sampling cyclone on the
techniques and whether quarter, half or rig. Approximately 25% of the original
and sample all core taken. sample retained. Duplicate samples were
preparation collected at every 20th sample. The drill
If non-core, whether riffled, rods and cyclone were routinely cleaned
tube sampled, rotary split, between holes using pressurised water to
etc and whether sampled wet avoid inter-hole contamination. The sample
or dry. size is considered appropriate for the grain
size of the material because the grade of HM
For all sample types, the is measured in per cent, and a 2.5-5kg sample
nature, quality and contains in excess of 50 million grains of
appropriateness of the sample sand.
preparation technique.
The sample preparation process departed from
Quality control procedures standard mineral sand practices in one
adopted for all sub-sampling respect; the samples were not oven dried
stages to maximise prior to de-sliming, to prevent clay minerals
representivity of samples. from baking onto the HM grains (because the
HM fractions were to be used in further
Measures taken to ensure that mineralogical test work). Instead, a
the sampling is separate sample was split and dried to
representative of the in-situ determine moisture content, which was
material collected, including accounted for mathematically.
for instance results for
field duplicate/second-half Pre-soaking of the sample TSPP dispersant
sampling. solution ensured a more efficient de-sliming
process and to avoid potentially
Whether sample sizes are under-reporting slimes content.
appropriate to the grain size
of the material being
sampled.
Quality of The nature, quality and The assay process employed by Base Resources
assay data appropriateness of the includes a Sample Preparation stage,
and assaying and laboratory completed by BTL staff, followed by a heavy
laboratory procedures used and whether liquid separation (using lithium
tests the technique is considered polytungstate: SG = 2.85g/cm3), completed at
partial or total. Kwale Operations' site laboratory.
For geophysical tools, Recent improvements to the sample preparation
spectrometers, handheld XRF stage were made to ensure industry best
instruments, etc, the practice and to deliver a high degree of
parameters used in confidence in the results. These included
determining the analysis the following:
including instrument make and
model, reading times, * A formalised process flow was generated,
calibrations factors applied posted in all sample preparation areas
and their derivation, etc. and used to train and monitor sample
preparation staff.
Nature of quality control * Regular monitoring was completed by BTL
procedures adopted (e.g., senior geology staff.
standards, blanks, * Field samples were left in their bags for
duplicates, external initial air-drying to avoid sample loss.
laboratory checks) and * TSPP was introduced to decrease attrition
whether acceptable levels of time and improve slimes recovery.A range
accuracy (i.e., lack of bias) of attrition times (with 5% TSPP) were
and precision have been trialled and plotted against slimes
established. recovery figures to determine optimum
attrition time (15 minutes).
* Staff were trained to use paint brushes
and water spray rather than manipulate
sample through slimes screen by hand to
remove the potential for screen damage.
* A calibration schedule was introduced for
scales used in the sample preparation
stage.
* Samples prepared and submitted
systematically in 40 -sample batches,
with each batch routinely containing QC
samples - one standard, two field
duplicates and two lab duplicates.
* Slimes screen number recorded to isolate
batches should re-assay be required due
to poor adherence to procedure or to
identify screen damage.
* Various quality control samples were
submitted routinely to assure assay
quality. A total of 95 field duplicates,
95 sample prep duplicates, 47 field
standard samples, 61 lab repeats, and an
unspecified number of internal standards,
repeats and blanks have been assayed at
Kwale Operations' site laboratory.
Verification The verification of The Bumamani deposit is a moderate to low HM
of sampling significant intersections by grade, dunal-style accumulation that does not
and assaying either independent or carry excessive mineralisation or suffer from
alternative company 'nugget' effects, typical of other
personnel. commodities.
The use of twinned holes. An external audit validation was completed
for the HM analyses included in the 2021
Documentation of primary Bumamani Mineral Resources estimate by IHC
data, data entry procedures, Robbins in 2020.
data verification, data
storage (physical and A total of ten twin drill holes were
electronic) protocols. completed between the 2017 and 2018 drilling
program, representing about 5.5% of the total
Discuss any adjustment to drillholes. These twins were used to quantify
assay data. short-range variability in geological
character and grade intersections and were
placed throughout the deposit.
The spatially well-represented twin hole
paired data shows very good correlation
considered material to the integrity/quality
of the resource data.
Location of Accuracy and quality of Proposed drill holes were sited on the ground
data points surveys used to locate drill using hand-held GPS. After drilling,
holes (collar and down-hole surveyors recorded collar positions via DGPS
surveys), trenches, mine RTK unit registered to local base stations.
workings and other locations The accuracy of the DGPS unit is stated at
used in Mineral Resource 0.02m in the X, Y and Z axes.
estimation.
The survey geodetic datum utilised was UTM
Specification of the grid Arc 1960, used in E. Africa. Arc 1960
system used. references the Clark 1880 (RGS) ellipsoid and
the Greenwich prime meridian. All survey
Quality and adequacy of data used in the 2021 Bumamani Mineral
topographic control. Resources estimate dataset has undergone a
transformation to the local mine grid from
the geodetic datum. The local Grid was
rotated at 42.5° which aligns the average
strike of the deposit with local North and is
useful for both grade interpolation and
mining reference during production.
All drill collars were projected to the local
LIDAR digital terrain model captured over the
resource area in 2018 at a 2x2m grid
spacing. This was performed prior to
interpretation and model construction to
eliminate any elevation disparities for the
block model construction.
Data spacing Data spacing for reporting of The drill data spacing from the 2017 and 2018
and Exploration Results. Bumamani Resource drilling programmes was
distribution nominally 50m X, 100m Y and 1.5m Z.
Whether the data spacing, and Variations from this spacing resulted from
distribution is sufficient to terrain difficulties or ground access issues.
establish the degree of
geological and grade This spacing and distribution is considered
continuity appropriate for sufficient to establish the degree of
the Mineral Resource and Ore geological and mineralisation continuity
Reserve estimation procedure appropriate for the resource estimation
(s) and classifications procedures and classifications applied.
applied.
A 1.5m downhole compositing has been applied
Whether sample compositing for HM, slimes and oversize in the
has been applied. interpolation processes. This is necessary in
Geovia Surpac software which cannot estimate
grades directly from the drillhole database.
Orientation Whether the orientation of With the geological setting being a layered
of data in sampling achieves unbiased dunal/fluviatile sequence, the orientation of
relation to sampling of possible the deposit mineralisation in general is
geological structures and the extent to sub-horizontal. All drill holes were
structure which this is known, orientated vertically to penetrate the
considering the deposit type. sub-horizontal mineralisation orthogonally.
If the relationship between Hole centres were spaced nominally at 50m.
the drilling orientation and This cross-profiles the dune so that
the orientation of key variation can be determined. Down hole
mineralised structures is intervals were nominated as 1.5m. This
considered to have introduced provides adequate sampling resolution to
a sampling bias, this should capture the distribution and variability of
be assessed and reported if geology units and mineralisation encountered
material. vertically down hole.
The orientation of the drilling is considered
appropriate for testing the horizontal and
vertical extent of mineralisation without
bias.
Sample The measures taken to ensure Sample residues from the prep stage were
security sample security. transferred to pallets and stored in a locked
storage facility beside the warehouse at
Kwale Operations.
Residues from the Kwale Operations site
laboratory were placed in labelled jars and
stored in numbered boxes. Boxes were placed
into a locked container beside the
laboratory.
Sample tables are housed on a secure,
network-hosted SQL database. Administration
privileges are limited to two BTL staff:
Exploration Superintendent and the Business
Applications Administrator.
Data is backed up every 12 hours and stored
in perpetuity on a secure, site backup
server. Data is also backed up on Maxwell
GeoServices servers in Perth.
Audits or The results of any audits or Base Resources' Resources Manager, Mr. Scott
reviews reviews of sampling Carruthers reviewed the Bumamani geological
techniques and data. interpretations, wireframes and assay and
mineralogy data interpolations. IHC Robbins
Geological Services Manager Greg Jones
validated the resource data and reviewed the
completed block model.
Section 2 Reporting of Exploration Results
(Criteria listed in the preceding section also apply to this section.)
Criteria JORC Code explanation Commentary
Mineral Type, reference name/number, The Bumamani deposit is situated on a
tenement and location and ownership Prospecting License (PL) 100% owned by Base
land tenure including agreements or Titanium Limited - PL/2018/0119 located in
status material issues with third Kwale County, Kenya. Base Titanium Limited
parties such as joint is a wholly owned subsidiary of Australian
ventures, partnerships, and UK-listed resources company, Base
overriding royalties, native Resources Limited.
title interests, historical
sites, wilderness or national The 88.7 km2 Prospecting License was granted
park and environmental on the 26th of May 2018 for a three-year
settings. term ending 25th May 2021.
The security of the tenure The PL is in good standing with the Kenya
held at the time of reporting Ministry of Petroleum & Mining at the time
along with any known of reporting, with all statutory reporting
impediments to obtaining a and payments up to date.
licence to operate in the
area. Local landowners are generally supportive of
exploration activities with over 90% of
planned holes drilled.
The existing Special Mining Lease 23 lies
within the Prospecting license area and
covers the Kwale Central deposit and some of
the Kwale South deposit but does not include
the Bumamani deposit. The Kenya Mining Act
2016 includes provision for the amendment of
an existing SML and for the conversion of an
existing PL to SML.
Exploration Acknowledgment and appraisal No known prior exploration has been
done by other of exploration by other undertaken by other parties.
parties parties.
Geology Deposit type, geological The Bumamani deposit is part of the
setting and style of extensive coastal Plio-Pleistocene Magarini
mineralisation. Formation, which comprises aeolian dunal
sands and clay-rich fluviatile units that
overlie down-faulted Jurassic and Tertiary
formations.
The presence of a thin, discontinuous
laterite layer seen at the base of the dune
sands is considered to indicate a change of
climate in contradistinction to the
underlying fluviatile sediments.
These units are locally enriched with heavy
minerals, primarily ilmenite, rutile and
zircon as well as significant silicate
gangue in the lower fluviatile units. The
hinterland 'Mozambique Belt' metamorphic
formations are considered the likely HM feed
source for the Kwale deposits.
Exploration along the Kenyan coastline is
yet to be successful in terms of mineralised
paleo-strandlines related to fossil marine
terraces, perhaps due to low wave energy
levels caused by the fringing reef acting as
a breakwater, thus preventing effective HM
winnowing and trapping.
Drill hole A summary of all information Drilling by year (max, min and average
Information material to the understanding depths) used for the resource model build
of the exploration results are as follows:
including a tabulation of the See drill hole location plan, Figures 9 and
following information for all 10.
Material drill holes:
All drill holes drilled vertically.
If the exclusion of this All collars projected to the LIDAR surface
information is justified on DTM
the basis that the
information is not Material Exploration results are not being reported
and this exclusion does not at this time.
detract from the
understanding of the report,
the Competent Person should
clearly explain why this is
the case.
Data In reporting Exploration Exploration results are not being reported
aggregation Results, weighting averaging at this time.
methods techniques, maximum and/or
minimum grade truncations No bottom and top cut grades were employed.
(e.g., cutting of high
grades) and cut-off grades No equivalent values were used.
are usually Material and
should be stated. No aggregation of short length samples used
as sample interval was consistently 1.5m.
Where aggregate intercepts
incorporate short lengths of
high-grade results and longer
lengths of low-grade results,
the procedure used for such
aggregation should be stated
and some typical examples of
such aggregations should be
shown in detail.
The assumptions used for any
reporting of metal equivalent
values should be clearly
stated.
Relationship These relationships are The deposit sequences are sub-horizontal,
between particularly important in the and the vertically inclined holes are a fair
mineralisation reporting of Exploration representation of true thickness.
widths and Results.
intercept
lengths If the geometry of the
mineralisation with respect
to the drill hole angle is
known, its nature should be
reported.
If it is not known and only
the down hole lengths are
reported, there should be a
clear statement to this
effect (e.g., 'down hole
length, true width not
known').
Diagrams Appropriate maps and sections See figures 8-11.
(with scales) and tabulations
of intercepts should be
included for any significant
discovery being reported
These should include, but not
be limited to a plan view of
drill hole collar locations
and appropriate sectional
views.
Balanced Where comprehensive reporting Exploration results are not being reported
reporting of all Exploration Results is at this time.
not practicable,
representative reporting of
both low and high grades and/
or widths should be practiced
to avoid misleading reporting
of Exploration Results.
Other Other exploration data, if The proprietary MinMod mineralogy technique,
substantive meaningful and material, developed and employed by Base Resources,
exploration should be reported including comprises an XRF analysis of the magnetic
data (but not limited to): and non-magnetic fractions of each composite
geological observations; or sample, the results from which are then
geophysical survey results; back-calculated to determine in-ground
geochemical survey results; mineralogy. MinMod represents an
bulk samples - size and improvement on the previous method (GeoMod)
method of treatment; that was not as effective at determining
metallurgical test results; accessory minerals in the Kwale assemblage.
bulk density, groundwater, MinMod has been validated by external
geotechnical and rock quantitative analysis (QEMSCAN and SEM EDX)
characteristics; potential and is considered sufficiently certified to
deleterious or contaminating support quoted resource confidence in this
substances. report.
Further work The nature and scale of Test pits for bulk sample mineralogy test
planned further work (e.g., work.
tests for lateral extensions
or depth extensions or Generation of more Ore4 downhole composites
large-scale step-out for MinMod mineralogy.
drilling).
Infill drilling to improve Mineral Resource
Diagrams clearly highlighting confidence in the Indicated and Inferred
the areas of possible areas.
extensions, including the
main geological Drilling of the Magaoni prospect which is a
interpretations and future northern extension of the Bumamani Deposit.
drilling areas, provided this
information is not
commercially sensitive.
Section 3 Estimation and Reporting of Mineral Resources
(Criteria listed in section 1, and where relevant in section 2, also apply to
this section.)
Criteria JORC Code explanation Commentary
Database Measures taken to ensure that Field data was captured in LogChief logging
integrity data has not been corrupted application and automatically validated
by, for example, through reference to pre-set library table
transcription or keying configurations.
errors, between its initial
collection and its use for Typing or logging code errors, duplication
Mineral Resource estimation of key identifiers (e.g., HOLE_ID, SAMP_ID)
purposes. and conflicts in related tables (e.g.,
down-hole depth) are quarantined by the
Data validation procedures software and require resolving immediately
used. before logging can proceed.
The SQL Database also has identical
automated validation features. Data import
is unsuccessful until these data issues are
resolved.
Field logging and survey data from the SQL
database were imported into Geovia Surpac
for database build and sectional
interrogation.
Validation steps included a visual
interrogation of collar versus geology
depths, a review of hole locations against
the drilling plan and a check for missing or
duplicated logged fields and outliers. Any
spurious or questionable entries were
resolved by the supervising Geologist.
At the completion of each hole, an entry was
made to the hand-written drilling diary. The
diary recorded the hole name, date, depth,
number of samples, time of start and finish,
a description of the location of the hole in
relation to the last hole and other things.
Such a diary provides valuable evidence if
there is an error in-hole naming or
surveying.
Several validation checks were made of
sample preparation data to ensure accurate
data entry and application of correct
procedure by BTL staff. This included:
* comparison of pre- versus post-oven
weights
* comparison of split weight versus
de-slimed weight
* comparison of split weight versus field
sample weight
* all sample preparation data were sorted
by each individual field and outliers
investigated
Assay results were delivered via email in 45
sample batches from the Kwale Operations
site laboratory. These were in the form of
CSV text files and imported by batch number
directly into the SQL database tables where
pre-set algorithms converted weights to
percentages and removed the moisture
content. The calculated assay results were
then checked manually for missing records
and out of range or unrealistic values.
Site visits Comment on any site visits Base Resources' Resources Manager Scott
undertaken by the Competent Carruthers, the Competent Person, has
Person and the outcome of visited the site several times to review
those visits. assaying, geological interpretation and
resource estimation processes, which are
If no site visits have been considered appropriate.
undertaken indicate why this
is the case.
Geological Confidence in (or conversely, The geological interpretation and zoning
interpretation the uncertainty of) the were completed by the BTL Exploration
geological interpretation of Superintendent by considering field logs,
the mineral deposit. assays, microscopic HM sink descriptions and
mineralogy data.
Nature of the data used and
of any assumptions made. The data spacing for the project is
considered sufficient for grade and
The effect, if any, of mineralogical continuity.
alternative interpretations
on Mineral Resource Two mineralised geological zones and a
estimation. basement zone were identified and were used
as constraints in the Mineral Resource
The use of geology in guiding estimation.
and controlling Mineral
Resource estimation. The uppermost zone at Bumamani, referred to
as Ore Zone 1, is a dark brown,
The factors affecting predominantly fine grained, well sorted
continuity both of grade and silty sand with very little induration. It
geology. is also characterised by clean, polished HM
with minimal gangue minerals.
Ore Zone 4, underlying Ore Zone 1 is a
sandy-clay fluviatile unit with low-level
sorting and common lateritic fragments. The
HM from this zone contains more lateritic
aggregates.
The Basement zone is a low-grade, clay rich,
fluviatile unit with a difficult to
impossible washability. The HM from this
zone is notably enriched in gangue
silicates.
For Ore Zones 1 and 4, a strong correlation
between the field logs, HM sink logs and XRF
oxide chemistry and QEMSCAN mineralogy gives
confidence to these interpretations.
Dimensions The extent and variability of The Bumamani Mineral Resource is
the Mineral Resource approximately 1,600m along strike and
expressed as length (along 500-700m across strike on average. The
strike or otherwise), plan deposit thickness averages 10m.
width, and depth below
surface to the upper and
lower limits of the Mineral
Resource.
Estimation and The nature and The Bumamani Mineral Resource estimation was
modelling appropriateness of the undertaken using Geovia Surpac version 6.8
techniques estimation technique(s) software.
applied and key assumptions,
including treatment of Inverse Distance Weighting to the power of
extreme grade values, three was used to interpolate assay grades
domaining, interpolation (HM, Slimes, Oversize) from the assay
parameters and maximum composite string file.
distance of extrapolation
from data points. If a Nearest Neighbour was used to interpolate
computer assisted estimation the mineralogy data from the mineralogy
method was chosen include a composite string file.
description of computer
software and parameters used. This is the maiden Mineral Resource estimate
for the Bumamani deposit and no previous
The availability of check estimates, or mining production records have
estimates, previous estimates been prepared by Base Resources.
and/or mine production
records and whether the No assumptions have been made as to the
Mineral Resource estimate recovery of by-products.
takes appropriate account of
such data. The parent cell size used in the grade
interpolation was half the average drill
The assumptions made hole spacing on the Y and X axes, which was
regarding recovery of 100m x 50m. The vertical thickness of the
by-products. cell was the nominal average drill sample
interval i.e., 1.5m.
Estimation of deleterious
elements or other non-grade No assumptions were made behind modelling of
variables of economic selected mining units.
significance (e.g., sulphur
for acid mine drainage No assumptions made about correlation
characterisation). between variables.
In the case of block model Validation was undertaken by swath plots,
interpolation, the block size population distribution analysis and visual
in relation to the average inspection.
sample spacing and the search
employed. The geological zones were used to control
the resource estimates. Grade
Any assumptions behind interpolations were controlled by ore zone.
modelling of selective mining
units.
Any assumptions about
correlation between
variables.
Description of how the
geological interpretation was
used to control the resource
estimates.
Discussion of basis for using
or not using grade cutting or
capping.
The process of validation,
the checking process used,
the comparison of model data
to drill hole data, and use
of reconciliation data if
available.
Moisture Whether the tonnages are The Mineral Resources estimate is on a dry
estimated on a dry basis or tonnes basis.
with natural moisture, and
the method of determination
of the moisture content.
Cut-off The basis of the adopted The economic cut-off of Kwale Operations is
parameters cut-off grade(s) or quality between 1% and 1.5% HM, and historically the
parameters applied. Kwale Operations Mineral Resources estimate
reporting focuses on a 1% HM cut-off grade.
Mining factors Assumptions made regarding It is assumed that the hydraulic mining
or assumptions possible mining methods, method used at the neighbouring Kwale
minimum mining dimensions and Operations would be used. Moderate slime
internal (or, if applicable, content and generally low levels of
external) mining dilution. It induration provide support for this mining
is always necessary as part method. This mining method is being
of the process of determining re-assessed as part of the Kwale North Dune
reasonable prospects for PFS.
eventual economic extraction
to consider potential mining
methods, but the assumptions
made regarding mining methods
and parameters when
estimating Mineral Resources
may not always be rigorous.
Where this is the case, this
should be reported with an
explanation of the basis of
the mining assumptions made.
Metallurgical The basis for assumptions or The existing concentrator and separation
factors or predictions regarding plant at Kwale Operations are assumed
assumptions metallurgical amenability. It capable of processing the material with
is always necessary as part recoveries expected to be aligned with
of the process of determining present production.
reasonable prospects for
eventual economic extraction
to consider potential
metallurgical methods, but
the assumptions regarding
metallurgical treatment
processes and parameters made
when reporting Mineral
Resources may not always be
rigorous. Where this is the
case, this should be reported
with an explanation of the
basis of the metallurgical
assumptions made.
Environmental Assumptions made regarding Coarse and fine tailings are intended to be
factors or possible waste and process co-disposed together. Initially, into the
assumptions residue disposal options. It Kwale Central pit void and subsequently into
is always necessary as part the Bumamani and Kwale North pit voids.
of the process of determining
reasonable prospects for
eventual economic extraction
to consider the potential
environmental impacts of the
mining and processing
operation. While at this
stage the determination of
potential environmental
impacts, particularly for a
greenfields project, may not
always be well advanced, the
status of early consideration
of these potential
environmental impacts should
be reported. Where these
aspects have not been
considered this should be
reported with an explanation
of the environmental
assumptions made.
Bulk density Whether assumed or A fixed dry bulk density of 1.7 (t/m3) was
determined. If assumed, the assumed for the Mineral Resource estimation,
basis for the assumptions. If based on operational experience of mining
determined, the method used, the Kwale Central Dune and South Dune
whether wet or dry, the deposits.
frequency of the
measurements, the nature,
size and representativeness
of the samples.
The bulk density for bulk
material must have been
measured by methods that
adequately account for void
spaces (vugs, porosity, etc),
moisture and differences
between rock and alteration
zones within the deposit.
Discuss assumptions for bulk
density estimates used in the
evaluation process of the
different materials.
Classification The basis for the The classification of the Indicated, and
classification of the Mineral Inferred Mineral Resources was supported by
Resources into varying the uniform grid spacing of drilling,
confidence categories. uncomplicated and consistent geology,
relatively good continuity of mineralisation
Whether appropriate account particularly along strike (and supported by
has been taken of all the domain controlled variography),
relevant factors (i.e., confidence in the down hole drilling data
relative confidence in and supporting criteria as noted above.
tonnage/grade estimations,
reliability of input data, As Competent Person, Base Resources'
confidence in continuity of Resources Manager Scott Carruthers considers
geology and metal values, that the result appropriately reflects a
quality, quantity and reasonable view of the deposit
distribution of the data). categorisation.
Whether the result
appropriately reflects the
Competent Person's view of
the deposit.
Audits or The results of any audits or An internal review was undertaken by Base
reviews reviews of Mineral Resource Resources' Resources Manager Scott
estimates. Carruthers with focus on the process and
output of the geology interpretation,
database integrity, whether wireframes
reflect the geological interpretation, and
model vs. drillhole grades. Mr. Carruthers
was satisfied with these facets.
An audit and review of the Bumamani resource
data and block model was undertaken by Greg
Jones of IHC Robbins. Mr. Jones was
satisfied with the integrity of the drilling
/assay data, block model interpolated values
and resource output.
Discussion of Where appropriate a statement Variography was undertaken to determine the
relative of the relative accuracy and drill hole support of the selected JORC
accuracy/ confidence level in the classification.
confidence Mineral Resource estimate
using an approach or Validation of the model vs drill hole grades
procedure deemed appropriate by direct observation and comparison of the
by the Competent Person. For results on screen.
example, the application of
statistical or geostatistical The resource statement is a global estimate
procedures to quantify the for the entire known extent of the Bumamani
relative accuracy of the deposit within the tenement area.
resource within stated
confidence limits, or, if
such an approach is not
deemed appropriate, a
qualitative discussion of the
factors that could affect the
relative accuracy and
confidence of the estimate.
The statement should specify
whether it relates to global
or local estimates, and, if
local, state the relevant
tonnages, which should be
relevant to technical and
economic evaluation.
Documentation should include
assumptions made and the
procedures used.
These statements of relative
accuracy and confidence of
the estimate should be
compared with production
data, where available.
Glossary
Competent The JORC Code requires that a Competent Person must be a Member or Fellow
Person of The Australasian Institute of Mining and Metallurgy, or of the
Australian Institute of Geoscientists, or of a 'Recognised Professional
Organisation'. A Competent Person must have a minimum of five years'
experience working with the style of mineralisation or type of deposit
under consideration and relevant to the activity which that person is
undertaking.
DTM Digital Terrain Model.
Indicated An Indicated Mineral Resource is that part of a Mineral Resource for which
Resource or quantity, grade (or quality), densities, shape and physical
Indicated characteristics are estimated with sufficient confidence to allow the
application of Modifying Factors in sufficient detail to support mine
planning and evaluation of the economic viability of the deposit.
Inferred An Inferred Mineral Resource is that part of a Mineral Resource for which
Resource or quantity and grade (or quality) are estimated on the basis of limited
Inferred geological evidence and sampling. Geological evidence is sufficient to
imply but not verify geological and grade (or quality) continuity. It is
based on exploration, sampling and testing information gathered through
appropriate techniques from locations such as outcrops, trenches, pits,
workings and drill holes.
Inverse A statistical interpolation method whereby the influence of data points
distance within a defined neighbourhood around an interpolated point decreases as a
weighting function of distance.
JORC Code The Australasian Code for Reporting of Exploration Results, Mineral
Resources and Ore Reserves 2012 Edition, as published by the Joint Ore
Reserves Committee of The Australasian Institute of Mining and Metallurgy,
Australian Institute of Geoscientists and Minerals Council of Australia.
LIDAR survey LIDAR is a remote sensing technology that measures distance by
illuminating a target with a laser and analysing the reflected light to
produce a DTM.
Measured A Measured Mineral Resource is that part of a Mineral Resource for which
Resource or quantity, grade (or quality), densities, shape, and physical
Measured characteristics are estimated with confidence sufficient to allow the
application of Modifying Factors to support detailed mine planning and
final evaluation of the economic viability of the deposit.
Mineral Mineral Resources are a concentration or occurrence of solid material of
Resources economic interest in or on the Earth's crust in such form, grade (or
quality), and quantity that there are reasonable prospects for eventual
economic extraction. The location, quantity, grade (or quality),
continuity and other geological characteristics of a Mineral Resource are
known, estimated or interpreted from specific geological evidence and
knowledge, including sampling. Mineral Resources are sub-divided, in
order of increasing geological confidence, into Inferred, Indicated and
Measured categories.
Minmod A company developed mineralogy modelling technique, it comprises an XRF
analysis of the magnetic and non-magnetic fractions of each composite or
sample, the results from which are then back-calculated to determine
in-ground mineralogy.
QEMSCAN An acronym for Quantitative Evaluation of Materials by Scanning Electron
Microscopy, an integrated automated mineralogy and petrography solution
providing quantitative analysis of minerals and rocks.
QQ plot Quantile plot. Used to graphically compare data distributions.
RTK Real time kinematic DGPS uses a base station GPS at a known point that
communicates via radio with a roving unit so that the random position
error introduced by the satellite owners may be corrected in real time.
SEM, SEM EDX A Scanning Electron Microscope is a type of electron microscope that
produces images of a sample or minerals by scanning the surface with a
focused beam of electrons. EDX is short for energy dispersive X-ray and
is commonly used in conjunction with SEM.
Variography A geostatistical method that investigates the spatial variability and
dependence of grade within a deposit. This may also include a directional
analysis.
XRF analysis or A spectroscopic method used to determine the chemical composition of a
XRF material through analysis of secondary X-ray emissions, generated by
excitation of a sample with primary X-rays that are characteristic of a
particular element.
ENDS.
For further information contact:
James Fuller, Manager Communications and Investor Relations
Base Resources
Tel: +61 (8) 9413 7426
Mobile: +61 (0) 488 093 763
Email: jfuller@baseresources.com.au
UK Media Relations
Tavistock Communications
Jos Simson and Gareth Tredway
Tel: +44 (0) 207 920 3150
About Base Resources
Base Resources is an Australian based, African focused, mineral sands producer
and developer with a track record of project delivery and operational
performance. The company operates the established Kwale Operations in Kenya
and is developing the Toliara Project in Madagascar. Base Resources is an ASX
and AIM listed company. Further details about Base Resources are available at
www.baseresources.com.au
PRINCIPAL & REGISTERED OFFICE
Level 1, 50 Kings Park Road
West Perth, Western Australia, 6005
Email: info@baseresources.com.au
Phone: +61 (0)8 9413 7400
Fax: +61 (0)8 9322 8912
NOMINATED ADVISOR
RFC Ambrian Limited
Stephen Allen
Phone: +61 (0)8 9480 2500
BROKER
Berenberg
Matthew Armitt / Detlir Elezi
Phone: +44 20 3207 7800
END
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