REG - Cobra Resources PLC - Successful Production of First MREC from Boland
28/01/2025 07:00
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RNS Number : 8673U Cobra Resources PLC 28 January 2025
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28 January 2025
Cobra Resources plc
("Cobra" or the "Company")
Successful Production of First Mixed Rare Earth Carbonate from Boland
Industry stand-out grades with bottom quartile cost potential
Notice of Investor Q&A
Cobra (https://cobraplc.com/) (LSE: COBR)
(https://www.londonstockexchange.com/stock/COBR/cobra-resources-plc/company-page)
, the mineral exploration and development company advancing a potentially
world-class ionic Rare Earth Elements ("REEs") discovery at its Boland Project
("Boland") in South Australia, is pleased to announce that it has successfully
produced a potentially saleable mixed rare earth carbonate ("MREC") at
laboratory scale from its in situ recovery ("ISR") study on permeable ore from
Boland.
Details of next steps and a live investor Q&A on Thursday, 30 January 2025
appear further below.
Summary
· Exceptionally high grade: 62.4% of the MREC product is comprised of
Total Rare Earth Oxides ("TREO"), one of the highest TREO grades produced from
ionic REE projects globally
· High critical Heavy Rare Earth ("HREO") content: industry standout
HREO quantity of 14.5% of MREC
· Low impurities: low elemental impurities of 3.13% with low levels of
uranium (34 ppm) and thorium (<10 ppm)
· High recoveries with optimisation upside: final ore to MREC
recoveries of 59% Magnet Rare Earths ("MREO") and 55% HREO, optimisation tests
demonstrate considerable increases to HREO recoveries further improving
product value
· High value return: based on treated sample grade of 4,447ppm TREO,
~4.2kg of MREC could be produced from one tonne of Boland ore at this grade
· Validation of favourable mining method: ionic recoveries through
controlled ISR, eliminating high capital costs and challenges associated with
the mining and handling of clay ores. This proof-of-concept highlights the
potential for Boland to be a bottom quartile, environmentally considerate
source of strategic metals
· Maiden MREC product a precursor to offtake discussions
· Results from 54 resource-focused drillholes expected during February
2025
Rupert Verco, Managing Director of Cobra, commented:
"We are delighted with the results of our first product sample from Boland.
This is an exceptional milestone for the Company as it validates Boland's
potential bottom quartile cost operating metrics, owing to the
mineralisation's amenability to ISR, and confirms that a quality product can
be achieved through a simple, low-cost flowsheet.
Impurity removal is a very important aspect of any rare earth project. To
achieve such high purities with 62.4% of the MREC being rare earth oxides in
our first attempt is outstanding! Such a high purity product from a simple,
low-cost flow sheet is a clear demonstration of Boland's commercial potential.
Boland brings together stand-out ionic mineralisation and unique geology that
lends itself to low capital and operating costs. These features give us
growing confidence of a high margin future operation. Further process
optimisation shall focus on increasing the recovery of strategic heavy rare
earths that will further increase not only the value and margin of our product
but the project's strategic importance.
With stage 1 of our resource drilling programme completed, we look forward to
announcing initial drilling results during February. We are well placed to
demonstrate the significant scale of Boland with a further 7,500m of drilling
planned over the coming months. Additionally, we are well financed to rapidly
advance the development of the project and demonstrate significant upside that
we expect to translate to value for our shareholders."
Figure 1: MREC produced from bench scale ISR extraction from Boland core
CBSC0003 26.7 - 27.2m
Maiden Impurity Removal and Precipitation Programme
The results of the Company's initial trial product are exceptionally
encouraging as the TREO content within the carbonate is one of the highest
produced from ionic projects globally(1). Relatively low impurities and low
levels of uranium and thorium support the generation of a potentially saleable
product produced through the lowest cost form of mining from both an economic
and environmental perspective: ISR. Key points include:
· The Company engaged the Australian Nuclear Science and Technology
Organisation ("ANSTO") to determine the optimal flowsheet steps required to
produce an MREC sample
· Pregnant liquor from the Company's initial bench scale ISR study was
used for impurity removal and MREC precipitation:
o High-grade sample of 4,447 ppm TREO, including 865 ppm Nd(2)O(3) +
Pr(6)O(11) and 128 ppm Dy(2)O(3) + Tb(2)O(3)
o Achieved over 150 days (0.14 pore volumes per day) by decreasing the pH
from 7.1 to 3.0 through the addition of 0.5M ammonium sulphate (AMSUL)
(H(2)SO(4))
o Low acid consumption of 15 kg/t H(2)SO(4)
o Valuable MREO recoveries of 68% MREO
o Strategic HREO recoveries of 62% HREO
· ~580mls of pregnant liquor with a weighted pH of 3.95 was used to
evaluate impurity removal via two steps, carried out at room temperature and
using 150 g/L NH(4)HCO(3) solution as the neutralising agent
· Once the pH setpoint was reached in each step the mixture was
agitated for a further 15 minutes and then vacuum filtered. The solids were
then washed on the filter three times with deionised water and dried at
105(o)C. The solids were digested and analysed by ICP-OES and ICP-MS. Process
steps include:
o Step 1 - Neutralise to pH 4.9, to precipitate Fe
o Step 2 - Neutralise to pH 6.0, to precipitate the large majority of Al
o Step 3 - Neutralise to pH 7.5, to precipitate MREC
· At these pH levels, virtually all the Fe is rejected in the first
step and >99% of the Al is rejected by the second step
· First pass precipitation testing delivered high downstream recoveries
of:
o TREO 89%
o MREO 87%
o HREO 84%
· Exceptional proof-of-concept results for ISR with ore to final
product recoveries of:
o TREO 59%
o MREO 59%
o HREO 55%
· MREC is well weighted with strategic HREOs even with recoveries being
lower than the recoveries achieved in follow-up optimisation studies. Mixed
Rare Earth Oxide distribution shown in Table 1 below:
Table 1: Rare Earth Oxide distribution in Boland MREC in comparison to other
peer REE projects, expressed as weight percentage of MREC:
COBR.L VMM.AX(2) MEI.AX(3) BCM.AX(4) RDM.AX(5) VTM.AX(6)
REO Wt% Wt% Wt% Wt% Wt% Wt%
La2O3 9.5 26.7 33.0 19.2 21.6 0.1
CeO2 26.5 1.5 0.8 4.9 0.7 0.1
Pr6O11 2.7 5.0 4.9 3.9 4.2 0.0
Nd2O3 9.3 17.5 12.6 16.1 14.3 0.1
Sm2O3 1.0 1.9 1.4 2.5 1.8 0.1
Eu2O3 0.2 0.5 0.3 0.3 0.1 0.0
Gd2O3 1.3 1.3 0.9 1.6 1.1 0.2
Tb2O3 0.1 0.2 0.1 0.2 0.2 0.1
Dy2O3 0.7 0.7 0.5 0.8 0.6 0.7
Ho2O3 0.2 0.1 0.1 0.1 0.1 0.2
Er2O3 0.4 0.3 0.2 0.4 0.1 0.8
Tm2O3 0.0 0.0 0.0 0.1 0.0 0.1
Yb2O3 0.1 0.2 0.1 0.3 0.1 0.7
Lu2O3 0.0 0.0 0.0 0.1 0.0 0.1
Y2O3 10.5 4.2 2.6 4.8 3.8 9.0
TREO 62.4 60.0 57.3 55.3 48.7 12.5
MREO 12.8 23.4 18.1 21.0 19.2 0.9
LREO 48.9 52.6 52.7 46.7 42.6 0.5
HREO 14.5 7.4 4.7 8.6 6.2 12.0
· Impurity levels are low for a maiden product with ~3.13% elemental
impurities. The distribution of which is shown below:
Table 2: Boland MREC composition impurities expressed as elemental weight %
Impurity Wt%
Al 0.39
Ca 0.44
Fe 0.01
K 0.04
Mg 0.00
Mn 0.01
Na 0.21
Ni <0.5
P <0.5
S 0.71
Si 0.29
Zn 0.01
Sc 0.0109
U 0.0034
Th <0.001
Total 3.13
· Owing to flowsheet simplicity, upside remains in further
optimisation, aiming to reduce the loss of REE and increase HREO recovery
through pH adjustment, testing alternate lixiviants and neutralising agents
Significance of results
Both purity and TREO content are important factors in producing a quality
saleable product. The specifications of this initial product are promising
with the TREO content being the highest of several advancing REE projects
(refer to figure 2), with the MREC being well weighted with HREOs, even with
initial HREO recoveries being lower than optimisation leach tests.
Figure 2: Quantity (as percentage) of LREO and HREO reporting to industry MREC
products
Figure 3: Process flowsheet used to produce Boland's maiden MREC
Next steps
· Results from 54 resource focused aircore drill holes expected during
February
· Stage 2 resource drilling to commence upon receipt of Stage 1 results
· Further sonic core drilling over a greater footprint to support
density and permeability estimates (March - April)
· Finalisation of environmental baseline studies and permitting to
enable infield permeability tests (May)
· Engineering design of tracer study to confirm bench scale
permeabilities (May)
· Maiden Mineral Resource Estimate (June - July)
· Infield permeability testing (June - July)
Notice of Investor Q&A
Managing Director Rupert Verco will host a live webinar and Q&A session on
Thursday, 30 January 2025 at 10.30 a.m. GMT to discuss the significance of the
Company's first MREC production from Boland as well as next steps for the
project.
Investors and interested parties are invited to register via the link below
and submit questions before or during the live webinar. Follow the directions
on Cobra's investor hub to register:
https://investors.cobraplc.com/webinars/GyVwQe-investor-q-a-maiden-mixed-rare-earth-carbonate-success
(https://investors.cobraplc.com/webinars/GyVwQe-investor-q-a-maiden-mixed-rare-earth-carbonate-success)
A recording of the webinar will be made available on the Cobra website after
the event.
References:
1. Total Rare Earth content compared to publicly available MREC
specifications produced from ionic rare earth projects.
2. Viridis Mining & Minerals, Cupim South and Centro Sul. ASX
Announcement - 12(th) December 2024: Maiden mixed rare earth carbonate
('MREC') product from Southern Complex
3. Meteoric Resources, Caldeira. ASX Announcement - 29 February 2024:
First Mixed Rare Earth Carbonate (MREC) Produced for Caldeira REE Project
4. Brazilian Critical Minerals, Ema. ASX Announcement - 11(th) November
2024: High-value mixed rare earth product successfully produced from Ema
project
5. Red Metal, Sybella. ASX Announcement - 8(th) July 2024: Maiden trial
product from Sybella rare earth ore
6. Victory Metals, North Stanmore. ASX Announcement - 6 November 2023:
High value mixed rare earth carbonate produced
Boland Project
Cobra's unique and highly scalable Boland discovery is a strategically
advantageous ionic rare earth discovery where high grades of valuable HREOs
and MREOs occur concentrated in a permeable horizon confined by impermeable
clays. Bench scale ISR testing has confirmed that mineralisation is amenable
to ISR mining. ISR has been used successfully for decades within geologically
similar systems to recover uranium within South Australia. Results of this
metallurgical test work support that, with minor optimisation, ISR techniques
should enable non-invasive and low-cost production of critical REEs from
Cobra's Boland discovery.
Follow this link to watch a short video of CEO Rupert Verco explaining the
results released in this announcement:
https://investors.cobraplc.com/link/GyVlGr
(https://investors.cobraplc.com/link/GyVlGr)
Further information relating to Boland and these metallurgical results are
presented in the appendices.
Enquiries:
Cobra Resources plc via Vigo Consulting
Rupert Verco (Australia) +44 (0)20 7390 0234
Dan Maling (UK)
SI Capital Limited (Joint Broker) +44 (0)1483 413 500
Nick Emerson
Sam Lomanto
Global Investment Strategy (Joint Broker) +44 (0)20 7048 9437
James Sheehan james.sheehan@gisukltd.com
Vigo Consulting (Financial Public Relations) +44 (0)20 7390 0234
Ben Simons cobra@vigoconsulting.com
Kendall Hill
The person who arranged for the release of this announcement was Rupert Verco,
Managing Director of the Company.
Information in this announcement relates to exploration results that have been
reported in the following announcements:
· Wudinna Project Update: "Further Positive Metallurgy Results from
Boland Project", dated 16 December 2024
· Wudinna Project Update: "2(nd) Bench Scale ISR Study & £1.7M
Placing", dated 26 November 2024
· Wudinna Project Update: "ISR Bench Scale Study Completion", dated 4
November 2024
· Wudinna Project Update: "ISR bench scale study delivers exceptional
results", dated 1 October 2024
· Wudinna Project Update: "ISR bench scale update - Exceptionally high
recoveries with low impurities and low acid consumption; on path to disrupt
global supply
of heavy rare earths", dated 28 August 2024
· Wudinna Project Update: "ISR bench scale update -Further
metallurgical success at world leading ISR rare earth project", dated 11 July
2024
· Wudinna Project Update: "ISR bench scale update - Exceptional head
grades revealed", dated 18 June 2024
· Wudinna Project Update: "Re-Assay Results Confirm High Grades Over
Exceptional Scale at Boland", dated 26 April 2024
Competent Persons Statement
The information in this report that relates to metallurgical results is based
on information compiled by Cobra Resources and reviewed by Mr Conrad Wilkins
who is the Group Process Engineering Lead at Wallbridge Gilbert Aztec, a
Fellow of the Australian Institute of Mining and Metallurgy (FAusIMM),
Chartered Professional Engineer and Member of Engineers Australia (CPEng
MIEAust). Mr Wilkins has sufficient experience that is relevant to the
metallurgical testing which was undertaken to qualify as a Competent Person as
defined in the 2012 edition of the "Australasian Code for Reporting of
Exploration Results, Mineral Resources and Ore Reserves". Mr Wilkins consents
to the inclusion in this report of the matters based on this information in
the form and context in which it appears.
Information in this announcement has been assessed by Mr Rupert Verco, a
Fellow of the Australasian Institute of Mining and Metallurgy. Mr Verco is an
employee of Cobra and has more than 16 years' industry experience which is
relevant to the style of mineralisation, deposit type, and activity which he
is undertaking to qualify as a Competent Person as defined in the 2012 Edition
of the Australasian Code for Reporting Exploration Results, Mineral Resources
and Ore Reserves of JORC. This includes 12 years of Mining, Resource
Estimation and Exploration.
About Cobra
In 2023, Cobra discovered a rare earth deposit with the potential to re-define
the cost of rare earth production. The highly scalable Boland ionic rare earth
discovery at Cobra's Wudinna Project in South Australia's Gawler Craton is
Australia's only rare earth project amenable for in situ recovery (ISR) mining
- a low cost, low disturbance method enabling bottom quartile recovery costs
without any need for excavation or ground disturbance. Cobra is focused on
de-risking the investment value of the discovery by proving ISR as the
preferred mining method and testing the scale of the mineralisation footprint
through drilling.
Cobra's Wudinna tenements also contain extensive orogenic gold mineralisation,
including a 279,000 Oz gold JORC Mineral Resource Estimate, characterised by
low levels of over-burden, amenable to open pit mining.
Regional map showing Cobra's tenements in the heart of the Gawler Craton
Follow us on social media:
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Engage with us by asking questions, watching video summaries and seeing what
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Appendix 1: Background information - the Boland Project and ISR
· The Boland Project was discovered by Cobra in 2023. Mineralisation is
ionically bound to clays and organics within palaeochannel sands within the
Narlaby Palaeochannel
· Mineralisation occurs within a permeable sand within an aquifer that
is saltier than sea water and is confined by impermeable clays
· ISR is executed through engineered drillhole arrays that allow the
injection of mildly acidic ammonium sulphate lixiviants, using the confining
nature of the geology to direct and lower the acidity of the orebody. This
low-cost process enables mines to operate profitably at lower grades and lower
rates of recovery
· Once REEs are mobile in solution in groundwater, it is also possible,
from an engineering standpoint, to recover the solution to surface via
extraction drillholes, without any need for excavation or ground disturbance
· The capital costs of ISR mining are low as they involve no material
movements and do not require traditional infrastructure to process ore - i.e.
metals are recovered in solution
· Ionic mineralisation is highly desirable owing to its high weighting
of valuable HREOs and the cost-effective method in which REEs can be desorbed
· Ionic REE mineralisation in China is mined in an in-situ manner that
relies on gravity to permeate mineralisation. The style of ISR process is
unconfined and cannot be controlled, increasing the risk for environmental
degradation. This low-cost process has enabled China to dominate mine supply
of HREOs, supplying over 90% globally
· Confined aquifer ISR is successfully executed globally within the
uranium industry, accounting for more than 60% of the world's uranium
production. This style of ISR has temporary ground disturbance, and the ground
waters are regenerated over time
· Cobra is aiming to demonstrate the economic and environmental
benefits of recovering ionic HREOs through the more environmentally aquifer
controlled ISR - a world first for rare earths
Figure 4: Comparison between the Chinese and the proposed Boland process for
ISR mining of REEs
Appendix 2: JORC Code, 2012 Edition - Table 3
Criteria JORC Code explanation Commentary
Sampling techniques · Nature and quality of sampling (eg cut channels, random chips, or 2024
specific specialised industry standard measurement tools appropriate to the
minerals under investigation, such as down hole gamma sondes, or handheld XRF SONIC
instruments, etc). These examples should not be taken as limiting the broad
meaning of sampling. · Core was scanned by a SciAps X555 pXRF to determine sample
intervals. Intervals through mineralized zones were taken at 10cm. Through
· Include reference to measures taken to ensure sample representivity waste, sample intervals were lengthened to 50cm. Core was halved by knife
and the appropriate calibration of any measurement tools or systems used. cutting. XRF scan locations were taken on an inner surface of the core to
ensure readings were taken on fresh sample faces.
· Aspects of the determination of mineralisation that are Material to
the Public Report. Full core samples were submitted to Australian Nuclear Science and Technology
Organisation (ANSTO), Sydney for XRF analysis and to ALS Geochemistry
· In cases where 'industry standard' work has been done this would be Laboratory (Brisbane) on behalf of ANSTO for lithium tetraborate digest
relatively simple (eg 'reverse circulation drilling was used to obtain 1 m ICP-MS. The core was split in half along the vertical axis, and one half
samples from which 3 kg was pulverised to produce a 30 g charge for fire further split into 10 even fractions along the length of the half-core.
assay'). In other cases more explanation may be required, such as where there Additional sub-sampling, homogenisation and drying steps were performed to
is coarse gold that has inherent sampling problems. Unusual commodities or generate ~260 g (dry equivalent) samples for head assay according to the
mineralisation types (eg submarine nodules) may warrant disclosure of detailed laboratory internal protocols.
information.
Drilling techniques · Drill type (eg core, reverse circulation, open-hole hammer, rotary 2024
air blast, auger, Bangka, sonic, etc) and details (eg core diameter, triple or
standard tube, depth of diamond tails, face-sampling bit or other type, · Sonic Core drilling completed Star Drilling using 4" core with a
whether core is oriented and if so, by what method, etc). SDR12 drill rig. Holes were reamed to 6" or 8" to enable casing and screens to
be installed
Drill sample recovery · Method of recording and assessing core and chip sample recoveries and Aircore & RC
results assessed.
· Sample recovery was generally good. All samples were recorded for
· Measures taken to maximise sample recovery and ensure representative sample type, quality and contamination potential and entered within a sample
nature of the samples. log.
· Whether a relationship exists between sample recovery and grade and · In general, sample recoveries were good with 10 kg for each 1 m
whether sample bias may have occurred due to preferential loss/gain of interval being recovered from AC drilling.
fine/coarse material.
· No relationships between sample recovery and grade have been
identified.
· RC drilling completed by Bullion Drilling Pty Ltd using 5 ¾"
reverse circulation drilling techniques from a Schramm T685WS rig with an
auxiliary compressor
· Sample recovery for RC was generally good. All samples were
recorded for sample type, quality and contamination potential and entered
within a sample log.
· In general, RC sample recoveries were good with 35-50 kg for each
1 m interval being recovered.
· No relationships between sample recovery and grade have been
identified.
Sonic Core
· Sample recovery is considered excellent.
Logging · Whether core and chip samples have been geologically and
geotechnically logged to a level of detail to support appropriate Mineral
Resource estimation, mining studies and metallurgical studies. Sonic Core
· Whether logging is qualitative or quantitative in nature. Core (or · Logging was carried out in detail, determining lithology and
costean, channel, etc) photography. clay/ sand content. Logging intervals were lithology based with variable
interval lengths.
· The total length and percentage of the relevant intersections logged.
· All core drilled has been lithologically logged.
Sub-sampling techniques and sample preparation · If core, whether cut or sawn and whether quarter, half or all core
taken.
Sonic Drilling
· If non-core, whether riffled, tube sampled, rotary split, etc and
whether sampled wet or dry.
· For all sample types, the nature, quality and appropriateness of the · Field duplicate samples were taken nominally every 1 in 25
sample preparation technique. samples where the sampled interval was quartered.
· Quality control procedures adopted for all sub-sampling stages to · Blanks and Standards were submitted every 25 samples
maximise representivity of samples.
· Half core samples were taken where lab geochemistry sample were
· Measures taken to ensure that the sampling is representative of the taken.
in situ material collected, including for instance results for field
duplicate/second-half sampling. · In holes where column leach test samples have been submitted,
full core samples have been submitted over the test areas.
· Whether sample sizes are appropriate to the grain size of the
material being sampled.
Quality of assay data and laboratory tests · The nature, quality and appropriateness of the assaying and Sample Characterisation Test Work performed by the Australian Nuclear Science
laboratory procedures used and whether the technique is considered partial or and Technology Organisation (ANSTO)
total.
· For geophysical tools, spectrometers, handheld XRF instruments, etc,
the parameters used in determining the analysis including instrument make and · Full core samples were submitted to Australian Nuclear Science
model, reading times, calibrations factors applied and their derivation, etc. and Technology Organisation (ANSTO), Sydney for preparation and analysis. The
core was split in half along the vertical axis, and one half further split
· Nature of quality control procedures adopted (eg standards, blanks, into 10 even fractions along the length of the half-core. Additional
duplicates, external laboratory checks) and whether acceptable levels of sub-sampling, homogenisation and drying steps were performed to generate ~260
accuracy (ie lack of bias) and precision have been established. g (dry equivalent) samples for head assay according to the laboratory internal
protocols.
· Multi element geochemistry of solid samples were analysed at
ANSTO (Sydney) by XRF for the major gangue elements Al, Ca, Fe, K, Mg, Mn, Na,
Ni, P, Si, S, and Zn.
· Multi element geochemistry of solid samples were additionally
analysed at ALS Geochemistry Laboratory (Brisbane) on behalf of ANSTO by
lithium tetraborate digest ICP-MS and analysed for Ce, Dy, Er, Eu, Gd, Ho,
La, Lu, Nd, Pr, Sm, Tb, Th, Tm, U, Y and Yb.
· Reported assays are to acceptable levels of accuracy and
precision.
· Internal laboratory blanks, standards and repeats for rare earths
indicated acceptable assay accuracy.
· Samples retained for metallurgical analysis were immediately
vacuum packed, nitrogen purged and refrigerated.
· These samples were refrigerated throughout transport.
Metallurgical Leach Test Work performed by the Australian Nuclear Science and
Technology Organisation (ANSTO)
· ANSTO laboratories prepared ~80g samples for diagnostic leaches, a
443g sample for a slurry leach and a 660g sample for a column leach.
Sub-samples were prepared from full cores according to the laboratory internal
protocols. Diagnostic and slurry leaching were carried out in baffled leach
vessels equipped with an overhead stirrer and applying a 0.5 M (NH4)2SO4
lixiviant solution, adjusted to the select pH using H2SO4.
· 0.5 M H2SO4 was utilised to maintain the test pH for the duration of
the test, if necessary. The acid addition was measured.
· Thief liquor samples were taken periodically.
· At the completion of each test, the final pH was measured, the slurry
was vacuum filtered to separate the primary filtrate.
· The thief samples and primary filtrate were analysed as follows:
o ICP-MS for Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Mn, Nd, Pb, Pr, Sc, Sm, Tb, Th,
Tm, U, Y, Yb.
o ICP-OES for Al, Ca, Fe, K, Mg, Mn, Na, Si.
· The water wash was stored but not analysed.
· Column leaching was carried out in horizontal leaching column. The
column was pressurised with nitrogen to 6 bar and submerged in a temperature
controlled bath.
· A 0.5 M (NH4)2SO4 lixiviant solution, adjusted to the select pH using
H2SO4 was fed to the column at a controlled flowrate.
· PLS collected from the end of the column was weighed, the SH and pH
measured and the free acid concentration determined by titration. Liquor
samples were taken from the collected PLS and analysed as follows:
o ICP-MS for Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Mn, Nd, Pb, Pr, Sc, Sm, Tb, Th,
Tm, U, Y, Yb.
o ICP-OES for Al, Ca, Fe, K, Mg, Mn, Na, Si.
· The column leach test has been completed. Assays of the column have
adjusted head grades of the initial bench scale study. Recoveries have been
adjusted accordingly.
Verification of sampling and assaying · The verification of significant intersections by either independent · Sampling data was recorded in field books, checked upon
or alternative company personnel. digitising and transferred to database.
· The use of twinned holes. · Geological logging was undertaken digitally via the MX Deposit
logging interface and synchronised to the database at least daily during the
· Documentation of primary data, data entry procedures, data drill programme.
verification, data storage (physical and electronic) protocols.
· Compositing of assays was undertaken and reviewed by Cobra
· Discuss any adjustment to assay data. Resources staff.
· Original copies of laboratory assay data are retained digitally
on the Cobra Resources server for future reference.
· Samples have been spatially verified through the use of Datamine
and Leapfrog geological software for pre 2021 and post 2021 samples and
assays.
· Twinned drillholes from pre 2021 and post 2021 drill programmes
showed acceptable spatial and grade repeatability.
· Physical copies of field sampling books are retained by Cobra
Resources for future reference.
· Elevated pXRF grades were checked and re-tested where anomalous.
pXRF grades are semi quantitative.
Location of data points · Accuracy and quality of surveys used to locate drill holes (collar Pre 2021
and down-hole surveys), trenches, mine workings and other locations used in
Mineral Resource estimation. · Collar locations were pegged using DGPS to an accuracy of +/-0.5
m.
· Specification of the grid system used.
· Downhole surveys have been completed for deeper RC and diamond
· Quality and adequacy of topographic control. drillholes
· Collars have been picked up in a variety of coordinate systems
but have all been converted to MGA 94 Zone 53. Collars have been spatially
verified in the field.
· Collar elevations were historically projected to a geophysical
survey DTM. This survey has been adjusted to AHD using a Leica CS20 GNSS base
and rover survey with a 0.05 cm accuracy. Collar points have been re-projected
to the AHD adjusted topographical surface.
2021-onward
· Collar locations were initially surveyed using a mobile phone
utilising the Avenza Map app. Collar points recorded with a GPS horizontal
accuracy within 5 m.
· RC Collar locations were picked up using a Leica CS20 base and
Rover with an instrument precision of 0.05 cm accuracy.
· Locations are recorded in geodetic datum GDA 94 zone 53.
· No downhole surveying was undertaken on AC holes. All holes were
set up vertically and are assumed vertical.
· RC holes have been down hole surveyed using a Reflex TN-14 true
north seeking downhole survey tool or Reflex multishot
· Downhole surveys were assessed for quality prior to export of
data. Poor quality surveys were downgraded in the database to be excluded from
export.
· All surveys are corrected to MGA 94 Zone 53 within the MX Deposit
database.
· Cased collars of sonic drilling shall be surveyed before a
mineral resource estimate
Data spacing and distribution · Data spacing for reporting of Exploration Results. · Drillhole spacing was designed on transects 50-80 m apart.
Drillholes generally 50-60 m apart on these transects but up to 70 m apart.
· Whether the data spacing and distribution is sufficient to establish
the degree of geological and grade continuity appropriate for the Mineral · Additional scouting holes were drilled opportunistically on
Resource and Ore Reserve estimation procedure(s) and classifications applied. existing tracks at spacings 25-150 m from previous drillholes.
· Whether sample compositing has been applied. · Regional scouting holes are drilled at variable spacings designed
to test structural concepts
· Data spacing is considered adequate for a saprolite hosted rare
earth Mineral Resource estimation.
· No sample compositing has been applied
· Sonic core holes were drilled at ~20m spacings in a wellfield
configuration based on assumed permeability potential of the intersected
geology.
Orientation of data in relation to geological structure · Whether the orientation of sampling achieves unbiased sampling of · Aircore and Sonic drill holes are vertical.
possible structures and the extent to which this is known, considering the
deposit type.
· If the relationship between the drilling orientation and the
orientation of key mineralised structures is considered to have introduced a
sampling bias, this should be assessed and reported if material.
Sample security · The measures taken to ensure sample security. · Transport of samples to Adelaide was undertaken by a competent
independent contractor. Samples were packaged in zip tied polyweave bags in
bundles of 5 samples at the drill rig and transported in larger bulka bags by
batch while being transported.
· Refrigerated transport of samples to Sydney was undertaken by a
competent independent contractor. Samples were double bagged, vacuum sealed,
nitrogen purged and placed within PVC piping.
· There is no suspicion of tampering of samples.
Audits or reviews · The results of any audits or reviews of sampling techniques and data. · No laboratory audit or review has been undertaken.
· Genalysis Intertek and BV Laboratories Adelaide are NATA (National
Association of Testing Authorities) accredited laboratory, recognition of
their analytical competence.
Appendix 3: Section 2 reporting of exploration results
Criteria JORC Code explanation Commentary
Mineral tenement and land tenure status · Type, reference name/number, location and ownership including · RC drilling occurred on EL 6131, currently owned 100% by Peninsula
agreements or material issues with third parties such as joint ventures, Resources limited, a wholly owned subsidiary of Andromeda Metals Limited.
partnerships, overriding royalties, native title interests, historical sites,
wilderness or national park and environmental settings. · Alcrest Royalties Australia Pty Ltd retains a 1.5% NSR royalty over
future mineral production from licenses EL6001, EL5953, EL6131, EL6317 and
· The security of the tenure held at the time of reporting along with EL6489.
any known impediments to obtaining a licence to operate in the area.
· Baggy Green, Clarke, Laker and the IOCG targets are located within
Pinkawillinnie Conservation Park. Native Title Agreement has been negotiated
with the NT Claimant and has been registered with the SA Government.
· Aboriginal heritage surveys have been completed over the Baggy Green
Prospect area, with no sites located in the immediate vicinity.
· A Native Title Agreement is in place with the Barngarla People.
Exploration done by other parties · Acknowledgment and appraisal of exploration by other parties. · On-ground exploration completed prior to Andromeda Metals' work was
limited to 400 m spaced soil geochemistry completed by Newcrest Mining Limited
over the Barns prospect.
· Other than the flying of regional airborne geophysics and coarse
spaced ground gravity, there has been no recorded exploration in the vicinity
of the Baggy Green deposit prior to Andromeda Metals' work.
· Paleochannel uranium exploration was undertaken by various parties in
the 1980s and the 2010s around the Boland Prospect. Drilling was primarily
rotary mud with downhole geophysical logging the primary interpretation
method.
Geology · Deposit type, geological setting and style of mineralisation. · The gold and REE deposits are considered to be related to the
structurally controlled basement weathering of epidote- pyrite alteration
related to the 1590 Ma Hiltaba/GRV tectonothermal event.
· Mineralisation has a spatial association with mafic
intrusions/granodiorite alteration and is associated with metasomatic
alteration of host rocks. Epidote alteration associated with gold
mineralisation is REE enriched and believed to be the primary source.
· Rare earth minerals occur within the saprolite horizon. XRD analysis
by the CSIRO identifies kaolin and montmorillonite as the primary clay phases.
· SEM analysis identified REE bearing mineral phases in hard rock:
· Zircon, titanite, apatite, andradite and epidote.
· SEM analyses identifies the following secondary mineral phases in
saprock:
· Monazite, bastanite, allanite and rutile.
· Elevated phosphates at the base of saprock do not correlate to rare
earth grade peaks.
· Upper saprolite zones do not contain identifiable REE mineral phases,
supporting that the REEs are adsorbed to clay particles.
· Acidity testing by Cobra Resources supports that pH chemistry may act
as a catalyst for Ionic and Colloidal adsorption.
· REE mineral phase change with varying saprolite acidity and REE
abundances support that a component of REE bursary is adsorbed to clays.
· Palaeo drainage has been interpreted from historic drilling and
re-interpretation of EM data that has generated a top of basement model.
· Ionic REE mineralisation is confirmed through metallurgical
desorption testing where high recoveries are achieved at benign acidities
(pH4-3) at ambient temperature.
· Ionic REE mineralisation occurs in reduced clay intervals that
contact both saprolite and permeable sand units. Mineralisation contains
variable sand quantities that yield permeability and promote insitu recovery
potentail
Drillhole Information · A summary of all information material to the understanding of the · Metallurgical results being reported represent a small portion of the
exploration results including a tabulation of the following information for Boland target area. Coordinates for Wellfield drill holes are presented within
all Material drill holes: previous announcements covering exploration results and are referenced within
this release.
o easting and northing of the drill hole collar
o elevation or RL (Reduced Level - elevation above sea level in metres) of
the drill hole collar
o dip and azimuth of the hole
o down hole length and interception depth
o hole length.
· If the exclusion of this information is justified on the basis that
the information is not Material and this exclusion does not detract from the
understanding of the report, the Competent Person should clearly explain why
this is the case.
Data aggregation methods · In reporting Exploration Results, weighting averaging techniques, · Reported summary intercepts are weighted averages based on length.
maximum and/or minimum grade truncations (eg cutting of high grades) and
cut-off grades are usually Material and should be stated. · No maximum/ minimum grade cuts have been applied.
· Where aggregate intercepts incorporate short lengths of high grade · No metal equivalent values have been calculated.
results and longer lengths of low grade results, the procedure used for such
aggregation should be stated and some typical examples of such aggregations · Gold results are reported to a 0.3 g/t cut-off with a maximum of 2m
should be shown in detail. internal dilution with a minimum grade of 0.1 g/t Au.
· The assumptions used for any reporting of metal equivalent values · Rare earth element analyses were originally reported in elemental
should be clearly stated. form and have been converted to relevant oxide concentrations in line with
industry standards. Conversion factors tabulated below:
·
Element Oxide Factor
Cerium CeO(2) 1.2284
Dysprosium Dy(2)O(3) 1.1477
Erbium Er(2)O(3) 1.1435
Europium Eu(2)O(3) 1.1579
Gadolinium Gd(2)O(3) 1.1526
Holmium Ho(2)O(3) 1.1455
Lanthanum La(2)O(3) 1.1728
Lutetium Lu(2)O(3) 1.1371
Neodymium Nd(2)O(3) 1.1664
Praseodymium Pr(6)O(11) 1.2082
Scandium Sc(2)O(3) 1.5338
Samarium Sm(2)O(3) 1.1596
Terbium Tb(4)O(7) 1.1762
Thulium Tm(2)O(3) 1.1421
Yttrium Y(2)O(3) 1.2699
Ytterbium Yb(2)O(3) 1.1387
· The reporting of REE oxides is done so in accordance with industry
standards with the following calculations applied:
· TREO = La(2)O(3) + CeO(2) + Pr(6)O(11) + Nd(2)O(3) + Sm(2)O(3) +
Eu(2)O(3) + Gd(2)O(3) + Tb(4)O(7) + Dy(2)O(3) + Ho(2)O(3) + Er(2)O(3) +
Tm(2)O(3) + Yb(2)O(3) + Lu(2)O(3) + Y(2)O(3)
· CREO = Nd(2)O(3) + Eu(2)O(3) + Tb(4)O(7) + Dy(2)O(3) + Y(2)O(3)
· LREO = La(2)O(3) + CeO(2) + Pr(6)O(11) + Nd(2)O(3)
· HREO = Sm(2)O(3) + Eu(2)O(3) + Gd(2)O(3) + Tb(4)O(7) + Dy(2)O(3)
+ Ho(2)O(3) + Er(2)O(3) + Tm(2)O(3) + Yb(2)O(3) + Lu(2)O(3) + Y(2)O(3)
· MREO = Nd(2)O(3) + Pr(6)O(11) + Tb(4)O(7) + Dy(2)O(3)
· NdPr = Nd(2)O(3) + Pr(6)O(11)
· TREO-Ce = TREO - CeO(2)
· % Nd = Nd(2)O(3)/ TREO
· % Pr = Pr(6)O(11)/TREO
· % Dy = Dy(2)O(3)/TREO
· % HREO = HREO/TREO
· % LREO = LREO/TREO
· XRF results are used as an indication of potential grade only.
Due to detection limits only a combined content of Ce, La, Nd, Pr & Y has
been used. XRF grades have not been converted to oxide.
Relationship between mineralisation widths and intercept lengths · These relationships are particularly important in the reporting of · All reported intercepts at Boland are vertical and reflect true width
Exploration Results. intercepts.
· If the geometry of the mineralisation with respect to the drill hole · Exploration results are not being reported for the Mineral Resource
angle is known, its nature should be reported. area.
· If it is not known and only the down hole lengths are reported, there
should be a clear statement to this effect (eg 'down hole length, true width
not known').
Diagrams · Appropriate maps and sections (with scales) and tabulations of · Relevant diagrams have been included in the announcement.
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 · Exploration results are not being reported for the Mineral Resources
locations and appropriate sectional views. area.
Balanced reporting · Where comprehensive reporting of all Exploration Results is not · Not applicable - Mineral Resource and Exploration Target are defined.
practicable, representative reporting of both low and high grades and/or
widths should be practiced to avoid misleading reporting of Exploration · Exploration results are not being reported for the Mineral Resource
Results. area.
Other substantive exploration data · Other exploration data, if meaningful and material, should be · Refer to previous announcements listed in RNS for reporting of REE
reported including (but not limited to): geological observations; geophysical results and metallurgical testing
survey results; geochemical survey results; bulk samples - size and method of
treatment; metallurgical test results; bulk density, groundwater, geotechnical
and rock characteristics; potential deleterious or contaminating substances.
Further work · The nature and scale of planned further work (eg tests for lateral · The metallurgical testing reported in this announcement represents
extensions or depth extensions or large-scale step-out drilling). the first phase of bench scale studies to test the extraction of ionic REEs
via ISR processes.
· Diagrams clearly highlighting the areas of possible extensions,
including the main geological interpretations and future drilling areas, · ISR study 1 was performed to achieve a pH 3 whilst ISR study 2 was
provided this information is not commercially sensitive. performed at a pH of 2.
· Future metallurgical testing will focus on producing PLS under leach
conditions to conduct downstream bench-scale studies for impurity removal and
product precipitation.
· Hydrology, permeability and mineralogy studies are being performed on
core samples.
· Installed wells are being used to capture hydrology base line data to
support a future infield pilot study.
· Trace line tests shall be performed to emulate bench scale pore
volumes.
· The reporting of REE oxides is done so in accordance with industry
standards with the following calculations applied:
· TREO = La(2)O(3) + CeO(2) + Pr(6)O(11) + Nd(2)O(3) + Sm(2)O(3) +
Eu(2)O(3) + Gd(2)O(3) + Tb(4)O(7) + Dy(2)O(3) + Ho(2)O(3) + Er(2)O(3) +
Tm(2)O(3) + Yb(2)O(3) + Lu(2)O(3) + Y(2)O(3)
· CREO = Nd(2)O(3) + Eu(2)O(3) + Tb(4)O(7) + Dy(2)O(3) + Y(2)O(3)
· LREO = La(2)O(3) + CeO(2) + Pr(6)O(11) + Nd(2)O(3)
· HREO = Sm(2)O(3) + Eu(2)O(3) + Gd(2)O(3) + Tb(4)O(7) + Dy(2)O(3)
+ Ho(2)O(3) + Er(2)O(3) + Tm(2)O(3) + Yb(2)O(3) + Lu(2)O(3) + Y(2)O(3)
· MREO = Nd(2)O(3) + Pr(6)O(11) + Tb(4)O(7) + Dy(2)O(3)
· NdPr = Nd(2)O(3) + Pr(6)O(11)
· TREO-Ce = TREO - CeO(2)
· % Nd = Nd(2)O(3)/ TREO
· % Pr = Pr(6)O(11)/TREO
· % Dy = Dy(2)O(3)/TREO
· % HREO = HREO/TREO
· % LREO = LREO/TREO
· XRF results are used as an indication of potential grade only.
Due to detection limits only a combined content of Ce, La, Nd, Pr & Y has
been used. XRF grades have not been converted to oxide.
Relationship between mineralisation widths and intercept lengths
· These relationships are particularly important in the reporting of
Exploration Results.
· 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 (eg 'down hole length, true width
not known').
· All reported intercepts at Boland are vertical and reflect true width
intercepts.
· Exploration results are not being reported for the Mineral Resource
area.
Diagrams
· Appropriate maps and sections (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.
· Relevant diagrams have been included in the announcement.
· Exploration results are not being reported for the Mineral Resources
area.
Balanced reporting
· Where comprehensive reporting of all Exploration Results is not
practicable, representative reporting of both low and high grades and/or
widths should be practiced to avoid misleading reporting of Exploration
Results.
· Not applicable - Mineral Resource and Exploration Target are defined.
· Exploration results are not being reported for the Mineral Resource
area.
Other substantive exploration data
· Other exploration data, if meaningful and material, should be
reported including (but not limited to): geological observations; geophysical
survey results; geochemical survey results; bulk samples - size and method of
treatment; metallurgical test results; bulk density, groundwater, geotechnical
and rock characteristics; potential deleterious or contaminating substances.
· Refer to previous announcements listed in RNS for reporting of REE
results and metallurgical testing
Further work
· The nature and scale of planned further work (eg tests for lateral
extensions or depth extensions or large-scale step-out drilling).
· Diagrams clearly highlighting the areas of possible extensions,
including the main geological interpretations and future drilling areas,
provided this information is not commercially sensitive.
· The metallurgical testing reported in this announcement represents
the first phase of bench scale studies to test the extraction of ionic REEs
via ISR processes.
· ISR study 1 was performed to achieve a pH 3 whilst ISR study 2 was
performed at a pH of 2.
· Future metallurgical testing will focus on producing PLS under leach
conditions to conduct downstream bench-scale studies for impurity removal and
product precipitation.
· Hydrology, permeability and mineralogy studies are being performed on
core samples.
· Installed wells are being used to capture hydrology base line data to
support a future infield pilot study.
· Trace line tests shall be performed to emulate bench scale pore
volumes.
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