THIS ANNOUNCEMENT CONTAINS INSIDE
INFORMATION FOR THE PURPOSES OF ARTICLE 7 OF REGULATION 2014/596/EU
WHICH IS PART OF DOMESTIC UK LAW PURSUANT TO THE MARKET ABUSE
(AMENDMENT) (EU EXIT) REGULATIONS (SI 2019/310) ("UK MAR"). UPON
THE PUBLICATION OF THIS ANNOUNCEMENT, THIS INSIDE INFORMATION (AS
DEFINED IN UK MAR) IS NOW CONSIDERED TO BE IN THE PUBLIC
DOMAIN.
NOT FOR RELEASE, PUBLICATION OR
DISTRIBUTION, IN WHOLE OR IN PART, DIRECTLY OR INDIRECTLY IN OR
INTO THE UNITED STATES, AUSTRALIA, CANADA, JAPAN, THE REPUBLIC OF
SOUTH AFRICA OR ANY OTHER JURISDICTION WHERE TO DO SO WOULD
CONSTITUTE A VIOLATION OF THE RELEVANT LAWS OF SUCH
JURISDICTION.
4 November 2024
Cobra Resources
plc
("Cobra"
or the "Company")
ISR Bench Scale Study
Completion
Achieved high recoveries from
high grade ore through a mining process to deliver bottom quartile
operating costs
Cobra
(LSE: COBR), the mineral
exploration and development company advancing a potentially
world-class ionic Rare Earth Elements ("REEs") discovery at its
Boland Project in South Australia, is pleased to announce that
final recoveries have been achieved from its bench scale in situ
recovery ("ISR") testing. The study has confirmed that ISR is a
suitable mining technique to deploy at Boland, supporting the
Company's ambition to commercialise the ionic rare earths
project.
Highlights
·
Further recovery
increases have been achieved:
o Total Rare Earth Oxide ("TREO") recoveries increased from 50%
to 56% TREO
o Valuable Magnet Rare Earth Oxides ("MREO") recoveries
increased from 48% to 57%
MREO
o Strategic Heavy Rare Earth Oxides ("HREO") recoveries
increased from 43% to 50%
HREO
o Strong recoveries achieved by lowering the sample pH from 7.1
to 3.0
·
Low levels of
impurities (deleterious elements)
alongside low levels of acid consumption were reported
·
Flow sheet
development has been advanced: the
pregnant liquor produced from the test is being used to advance
metallurgical flowsheet development. Impurity removal tests are
currently underway which are expected to generate a sufficient
quantity of Mixed Rare Earth Carbonate ("MREC") to evaluate product
specifications and impurities
·
The low-cost, low-disturbance ISR recovery process
has been successfully demonstrated
Rupert Verco, CEO of Cobra,
commented:
"We're delighted to have completed bench scale in situ
recovery trials which have significantly increased our confidence
in ISR being the ideal mining method to cost effectively extract
rare earths from Boland - just as it has been leveraged to recover
uranium from South Australian operations for many years. These
further improvements in recoveries validate the potential low cost
of production that Boland could deliver and, in the context of rare
earth projects, achieving 57% MREO recoveries from a high grade
(0.45% TREO) sample at such a benign acidity is a fantastic result.
In addition, achieving these recoveries through a process that
eliminates physical mining and clay treatment is truly exceptional.
Follow-up impurity removal tests will advance the development
of our flowsheet. We anticipate that the results of this work will
be available in 4-5 weeks where we expect to demonstrate the value
of Boland in the form of a saleable product.
We
are taking a strategic approach to demonstrating the significance
of our opportunity, carefully de-risking the project at every step
along the commercialisation pathway. We aim to demonstrate a
simple, low-cost process for impurity removal to produce a
high-purity product, well weighted with heavy rare earths of
crucial importance to modern technology and the global energy
transition."
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.
Cobra engaged the Australian Nuclear
Science and Technology Organisation ("ANSTO") to execute a detailed
work programme to confirm and optimise the recovery of REEs through
the ISR process. Highlights of the final results
include:
·
Low capital
mining process: the permeability of
the orebody was used to percolate lixiviant. A permeation rate of
0.14 pore volumes per day was achieved which is comparable to
operating ISR uranium mines. This demonstrates that geological
conditions can be used to mitigate the cost of capital
infrastructure for ore handling and processing
·
High desorption
recoveries to date: rare earths
commenced reporting to solution when the Pregnant Liquor Solution
("PLS") in the column dropped below pH 5.2 and rapidly continued
until the PLS reached pH 3.0. Final recoveries are:
o 56%
TREOs
o 57%
MREOs
o 50%
HREOs
·
Further recovery
upside: increased recoveries of
78% Pr, 86% Nd, 86% Dy and 87% Tb using a pH 2.0 lixiviant
supported by diagnostic tests across three composite
samples1
·
Low acid
consumption: no further acid
consumption beyond the previously reported total sulphuric acid
consumption of 15.0 kg per tonne of ore treated in column ISR
study
·
Low impurity
levels: low levels of impurities
(deleterious elements) compared to recovered rare earths support a
low cost, simple process for purification
Follow this link to watch a short
video of CEO Rupert Verco explaining the results released in this
announcement: https://investors.cobraplc.com/link/0rJk9P
Further information relating to
metallurgical results are presented in the appendices.
1 Please refer to the announcement dated 1 October 2024 for
details of optimisation recoveries.
Enquiries:
|
Cobra Resources plc
Rupert Verco (Australia)
Dan Maling (UK)
|
via Vigo
Consulting
+44 (0)20
7390 0234
|
|
SI
Capital Limited (Joint Broker)
Nick Emerson
Sam Lomanto
|
+44
(0)1483 413 500
|
|
Global Investment Strategy (Joint Broker)
James Sheehan
|
+44 (0)20
7048 9437
james.sheehan@gisukltd.com
|
|
Vigo
Consulting (Financial Public Relations)
Ben Simons
Kendall Hill
|
+44 (0)20
7390 0234
cobra@vigoconsulting.com
|
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: "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
·
Wudinna Project Update: "Drilling results from
Boland Prospect", dated 25 March 2024
·
Wudinna Project Update: "Historical Drillhole
Re-Assay Results", dated 27 February 2024
·
Wudinna Project Update: "Ionic Rare Earth
Mineralisation at Boland Prospect", dated 11 September
2023
·
Wudinna Project Update: "Exceptional REE Results
Defined at Boland", dated 20 June 2023
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. Cobra
is focused on de-risking the investment value of the discovery by
proving ISR as the preferred mining method which would eliminate
challenges associated with processing clays and provide Cobra with
the opportunity to define a low-cost pathway to
production.
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:
LinkedIn: https://www.linkedin.com/company/cobraresourcesplc
X (Twitter):
https://twitter.com/Cobra_Resources
Engage with us by asking questions,
watching video summaries and seeing what other shareholders have to
say. Navigate to our Interactive Investor hub here:
https://investors.cobraplc.com/
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https://investors.cobraplc.com/auth/signup
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 1: Comparison between
the Chinese and the proposed Boland process for ISR mining of
REEs
Appendix 2: ISR study process
and results
The bench scale ISR study conducted
by ANSTO is based on a process routinely implemented to demonstrate
the amenability of uranium ores to be mined via ISR. ISR is enabled
by orebody permeability. These characteristics enable multiple
steps to be removed from the traditional mining and processing. The
objective of the study was to demonstrate and identify optimal
parameters in which ISR could be utilised to minimise the economics
of recovering REEs. The test parameters are scaled to emulate the
actual field process. A photograph of the test sample is detailed
in Figure 2.
The ISR process occurs in two
phases:
1. Preconditioning: The period where
injection and extraction occurs to impregnate the orebody and
modify the acidity of the aquifer. It took approximately 10 pore
volumes (~80 days) to lower the pH from 7.1 to 5.7. Through this
period acid consumption occurred due to the presence of minor acid
consuming minerals. When the PLS pH dropped below pH 5.7, REEs
began reporting to the PLS
2. Extraction: When the acidity reaches a
point in which the ion exchange can occur, REE recovery commences.
In this circumstance, this occurred from pH 5.7. REEs reported to
the PLS during 10 pore volumes (~68 days)
Figure 2: ANSTO bench scale ISR
test
Results of the study
demonstrate:
·
Orebody
characteristics are amenable to ISR mining -
a maximum permeability rate of 0.16 pore volumes
per day which is comparable to permeability rates of operating
uranium mines
·
High ionic REE
recoveries of 56% TREO, 57% MREO and
50% HREO achieved by lowering the sample acidity to pH3
·
Low acid
consumption of 15.0 kg/t sulphuric
acid (H2SO4)
·
High purity REE
extraction: low impurity levels that
support a simple purification process. This enables further
optimisation to increase recoveries. PLS impurity concentrations
shown in the table below
Table 1: Achieved recoveries in
PLS (mg/L) of REE and impurities during the extraction phase of the
ISR process
|
TREY
|
Th
|
U
|
Al
|
Fe
|
Si
|
|
379
|
0.008
|
0.08
|
55
|
46
|
31
|
Figure 3: Cumulative recoveries
of REE to PLS plotted against PLS acidity
Table 2: Head grade and
subsequent recoveries of bench scale ISR testing
|
Hole ID
|
Sample ID
|
Sample Head Grade
ppm
|
|
TREO
|
Nd2O3
|
Pr6O11
|
Dy2O3
|
Tb2O3
|
|
CBSC0004
|
COBR-3
|
4,506
|
708
|
183
|
112
|
19
|
|
Bench
Scale ISR Recoveries
|
56%
|
61%
|
59%
|
35%
|
39%
|
Appendix 3: JORC Code, 2012
Edition - Table 1
|
Criteria
|
JORC Code explanation
|
Commentary
|
|
Sampling
techniques
|
·
Nature and
quality of sampling (eg cut channels, random chips, or specific
specialised industry standard measurement tools appropriate to the
minerals under investigation, such as down hole gamma sondes, or
handheld XRF instruments, etc). These examples should not be taken
as limiting the broad meaning of sampling.
·
Include
reference to measures taken to ensure sample representivity and the
appropriate calibration of any measurement tools or systems
used.
·
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 (eg '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 (eg submarine nodules)
may warrant disclosure of detailed information.
|
2024
SONIC
· Core was scanned by a SciAps X555 pXRF to determine sample
intervals. Intervals through mineralized zones were taken at 10cm.
Through waste, sample intervals were lengthened to 50cm. Core was
halved by knife cutting. XRF scan locations were taken on an inner
surface of the core to ensure readings were taken on fresh sample
faces.
Full core samples were submitted to
Australian Nuclear Science and Technology Organisation (ANSTO),
Sydney for XRF analysis and to ALS Geochemistry Laboratory
(Brisbane) on behalf of ANSTO for lithium tetraborate digest
ICP-MS. The core was split in half along the vertical axis, and one
half further split into 10 even fractions along the length of the
half-core. Additional sub-sampling, homogenisation and drying steps
were performed to generate ~260 g (dry equivalent) samples for head
assay according to the laboratory internal protocols.
|
|
Drilling
techniques
|
·
Drill type (eg
core, reverse circulation, open-hole hammer, rotary 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, whether core is oriented and if so, by what method,
etc).
|
2024
· Sonic
Core drilling completed Star Drilling using 4" core with a 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 results
assessed.
·
Measures taken
to maximise sample recovery and ensure representative nature of the
samples.
·
Whether a
relationship exists between sample recovery and grade and whether
sample bias may have occurred due to preferential loss/gain of
fine/coarse material.
|
Aircore & RC
· Sample
recovery was generally good. All samples were recorded for sample
type, quality and contamination potential and entered within a
sample log.
· In general, sample recoveries were good with 10 kg for each 1
m interval being recovered from AC drilling.
· 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.
·
Whether logging
is qualitative or quantitative in nature. Core (or costean,
channel, etc) photography.
·
The total length
and percentage of the relevant intersections
logged.
|
Sonic Core
· Logging was carried out in detail, determining lithology and
clay/ sand content. Logging intervals were lithology based with
variable interval lengths.
· 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.
·
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 sample
preparation technique.
·
Quality control
procedures adopted for all sub-sampling stages to maximise
representivity of samples.
·
Measures taken
to ensure that the sampling is representative of the in situ
material collected, including for instance results for field
duplicate/second-half sampling.
·
Whether sample
sizes are appropriate to the grain size of the material being
sampled.
|
Sonic Drilling
· Field duplicate samples were taken nominally every 1 in 25
samples where the sampled interval was quartered.
·
Blanks and Standards were
submitted every 25 samples
· Half core samples were taken where lab geochemistry sample
were taken.
· In
holes where column leach test samples have been submitted, full
core samples have been submitted over the test areas.
|
|
Quality of assay data and
laboratory tests
|
·
The nature,
quality and appropriateness of the assaying and laboratory
procedures used and whether the technique is considered partial or
total.
·
For geophysical
tools, spectrometers, handheld XRF instruments, etc, the parameters
used in determining the analysis including instrument make and
model, reading times, calibrations factors applied and their
derivation, etc.
·
Nature of
quality control procedures adopted (eg standards, blanks,
duplicates, external laboratory checks) and whether acceptable
levels of accuracy (ie lack of bias) and precision have been
established.
|
Sample Characterisation Test Work
performed by the Australian Nuclear Science and Technology
Organisation (ANSTO)
· Full core samples were submitted to Australian Nuclear Science and
Technology Organisation (ANSTO), Sydney for preparation and
analysis. The core was split in half along the vertical axis, and
one half further split into 10 even fractions along the length of
the half-core. Additional sub-sampling, homogenisation and drying
steps were performed to generate ~260 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.
·
1 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 are being taken to confirm PLS assays
|
|
Verification of sampling and
assaying
|
·
The verification
of significant intersections by either independent or alternative
company personnel.
·
The use of
twinned holes.
·
Documentation of
primary data, data entry procedures, data verification, data
storage (physical and electronic) protocols.
·
Discuss any
adjustment to assay data.
|
· Sampling data was recorded in field books, checked upon
digitising and transferred to database.
· Geological logging was undertaken digitally via the MX Deposit
logging interface and synchronised to the database at least daily
during the drill programme.
·
Compositing of assays was undertaken
and reviewed by Cobra 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 and down-hole
surveys), trenches, mine workings and other locations used in
Mineral Resource estimation.
·
Specification of
the grid system used.
·
Quality and
adequacy of topographic control.
|
Pre 2021
· Collar
locations were pegged using DGPS to an accuracy of +/-0.5
m.
· Downhole surveys have been completed for deeper RC and diamond
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.
·
Whether the data
spacing and distribution is sufficient to establish the degree of
geological and grade continuity appropriate for the Mineral
Resource and Ore Reserve estimation procedure(s) and
classifications applied.
·
Whether sample
compositing has been applied.
|
·
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.
·
Additional scouting holes were drilled
opportunistically on existing tracks at spacings 25-150 m from
previous drillholes.
·
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 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.
|
·
Aircore and Sonic drill holes are
vertical.
|
|
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 4: 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 agreements or
material issues with third parties such as joint ventures,
partnerships, overriding royalties, native title interests,
historical sites, wilderness or national park and environmental
settings.
·
The security of
the tenure held at the time of reporting along with any known
impediments to obtaining a licence to operate in the
area.
|
· RC drilling occurred on EL 6131, currently owned 100% by
Peninsula Resources limited, a wholly owned subsidiary of Andromeda
Metals Limited.
·
Alcrest Royalties Australia Pty Ltd retains a 1.5%
NSR royalty over future mineral production from licenses EL6001,
EL5953, EL6131, EL6317 and EL6489.
· 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 exploration
results including a tabulation of the following information for all
Material drill holes:
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.
|
·
Exploration results being reported represent a
small portion of the Boland target area. Coordinates for Wellfield
drill holes are presented in Table 3.
|
|
Data aggregation
methods
|
·
In reporting
Exploration Results, weighting averaging techniques, maximum and/or
minimum grade truncations (eg cutting of high grades) and cut-off
grades are usually Material and should be stated.
·
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.
|
·
Reported summary intercepts are weighted averages
based on length.
·
No maximum/ minimum grade cuts have been
applied.
·
No metal equivalent values have been
calculated.
·
Gold results are reported to a 0.3 g/t cut-off
with a maximum of 2m internal dilution with a minimum grade of 0.1
g/t Au.
·
Rare earth element analyses were originally
reported in elemental form and have been converted to relevant
oxide concentrations in line with industry standards. Conversion
factors tabulated below:
·
|
Element
|
Oxide
|
Factor
|
|
Cerium
|
CeO2
|
1.2284
|
|
Dysprosium
|
Dy2O3
|
1.1477
|
|
Erbium
|
Er2O3
|
1.1435
|
|
Europium
|
Eu2O3
|
1.1579
|
|
Gadolinium
|
Gd2O3
|
1.1526
|
|
Holmium
|
Ho2O3
|
1.1455
|
|
Lanthanum
|
La2O3
|
1.1728
|
|
Lutetium
|
Lu2O3
|
1.1371
|
|
Neodymium
|
Nd2O3
|
1.1664
|
|
Praseodymium
|
Pr6O11
|
1.2082
|
|
Scandium
|
Sc2O3
|
1.5338
|
|
Samarium
|
Sm2O3
|
1.1596
|
|
Terbium
|
Tb4O7
|
1.1762
|
|
Thulium
|
Tm2O3
|
1.1421
|
|
Yttrium
|
Y2O3
|
1.2699
|
|
Ytterbium
|
Yb2O3
|
1.1387
|
·
The reporting of REE oxides is done so in
accordance with industry standards with the following calculations
applied:
· TREO =
La2O3 + CeO2 +
Pr6O11 + Nd2O3 +
Sm2O3 + Eu2O3 +
Gd2O3 + Tb4O7 +
Dy2O3 + Ho2O3 +
Er2O3 + Tm2O3 +
Yb2O3 + Lu2O3 +
Y2O3
· CREO =
Nd2O3 + Eu2O3 +
Tb4O7 + Dy2O3 +
Y2O3
· LREO =
La2O3 + CeO2 +
Pr6O11 +
Nd2O3
· HREO =
Sm2O3 + Eu2O3 +
Gd2O3 + Tb4O7 +
Dy2O3 + Ho2O3 +
Er2O3 + Tm2O3 +
Yb2O3 + Lu2O3 +
Y2O3
· MREO
= Nd2O3 +
Pr6O11 +
Tb4O7 +
Dy2O3
· NdPr =
Nd2O3 +
Pr6O11
· TREO-Ce = TREO - CeO2
· % Nd =
Nd2O3/ TREO
· % Pr =
Pr6O11/TREO
· % Dy =
Dy2O3/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.
· 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.
|
Table 3: Drillhole
coordinates
|
Prospect
|
Hole number
|
Grid
|
Northing
|
Easting
|
Elevation
|
|
Boland
|
CBSC0001
|
GDA94 /
MGA zone 53
|
6365543
|
534567
|
102.9
|
|
Boland
|
CBSC0002
|
GDA94 /
MGA zone 53
|
6365510
|
534580
|
104.1
|
|
Boland
|
CBSC0003
|
GDA94 /
MGA zone 53
|
6365521
|
534554
|
102.7
|
|
Boland
|
CBSC0004
|
GDA94 /
MGA zone 53
|
6365537
|
534590
|
105
|
|
Boland
|
CBSC0005
|
GDA94 /
MGA zone 53
|
6365528
|
534573
|
103.2
|