REG - Cobra Resources PLC - Drilling Results from Boland Prospect
25/03/2024 07:00
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RNS Number : 0297I Cobra Resources PLC 25 March 2024
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.
25 March 2024
Cobra Resources plc
("Cobra" or the "Company")
Drilling Results from Boland Prospect
Assays confirm high grade concentrations; modelled geology demonstrates
massive scale; high calculated permeability supports in situ recovery
Cobra (https://cobraplc.com/) (LSE: COBR)
(https://www.londonstockexchange.com/stock/COBR/cobra-resources-plc/company-page)
, an exploration company focused on the Wudinna Project ("Wudinna") in South
Australia, is pleased to announce that preliminary results from recent sonic
core drilling at the Boland ionic rare earths ("REE") prospect further
demonstrate that the discovery could be a world class source of magnet and
heavy rare earths.
Cobra confirmed ionic REE metallurgical recoveries at Boland in 2023 and
recent sonic core drilling has provided greater geological detail which
confirms the Company's thesis that grade concentrations are high,
mineralisation is amenable to low-cost extraction via in situ recovery
("ISR"), and the discovery has exceptional province scale potential. Results
demonstrate:
· High grade concentrations across three zones of mineralisation
· High grades in geological formations with high permeabilities
amenable to ISR
· Modelled mineralised units support exceptional scale
Rupert Verco, CEO of Cobra, commented:
"These results are sensational! It is pleasing to see our value proposition
materialise, and these results, coupled with the excellent metallurgical
recoveries achieved last year, demonstrate Boland is not only unique but world
class.
The value of in situ recovery cannot be overestimated. It is the preferred
mining method from scale, cost and environmental perspectives and we are now
positioned to be industry leaders in applying this form of mining long used
for uranium to ionic rare earth mineralisation.
Whilst the Brazilian ionic rare earth projects have captured market interest,
our results are comparable in grade, scale and metallurgy and the Boland
prospect's advantage is the unique geology that makes it amenable to ISR. Our
forward work programme is designed to demonstrate the project's commercial
advantage as we continue to define scale, grade upside, and highlight the
value of ISR."
Highlights
· High grade concentrations across three zones of mineralisation:
results received from three holes intersect three zones of mineralisation that
yield length-weighted averages of:
o Zone 1: 3.1m at 1,007 ppm Total Rare Earth Oxides ("TREO"), where
Nd(2)O(3) + Pr(6)O(11) totals 212 ppm and Dy(2)O(3) + Tb(2)O(3) totals 23.5
ppm (Magnet Rare Earth Oxides ("MREO") 23.4%, Heavy Rare Earth Oxides ("HREO")
17%) from 15.6m
o Zone 2: 1.9m at 1,043 ppm TREO, where Nd(2)O(3) + Pr(6)O(11) totals 205
ppm and Dy(2)O(3) + Tb(2)O(3) totals 22 ppm (MREO 22%, HREO 18%) from ~20.5m
o Zone 3: 0.6m at 1,538 ppm TREO where Nd(2)O(3) + Pr(6)O(11) totals 305 ppm
and Dy(2)O(3) + Tb(2)O(3) totals 52 ppm (MREO 23%, HREO 28%) from ~26.6m
· High grades with high permeabilities: the highest grade assay of
4,608 ppm TREO, where Nd(2)O(3) + Pr(6)O(11) totals 934 ppm and Dy(2)O(3) +
Tb(2)O(3) totals 91 ppm (MREO 24%, HREO 27%), comes from Zone 3, where:
o Particle size distribution analysis supports high calculated
permeabilities with 67.6% of the mineralised interval having a particle size
greater than 0.1mm (fine sand)
o Particle size distribution yields a high calculated transmissivity of
135-275 m/day(1) and is very supportive of high ISR success
o The highest ionic recoveries were yielded: 79% Tb, 67% Dy, 60% Nd and 47%
Pr using a simple AMSUL wash at pH3
Further sizing analysis is underway for Zones 1 and 2
· Modelled mineralised units support exceptional scale: mineralised
host units have been modelled across the palaeochannel at Boland, where:
o The geological formation hosting Zone 1 mineralisation is mapped across
~128,000,000m(2)
o The geological formation hosting Zone 2 mineralisation is mapped across
~58,000,000m(2)
o The geological formation hosting Zone 3 mineralisation is mapped across
~139,000,000m(2)
· Modelling is based on the downhole geophysical responses attributed
to each mineralised zone in alignment with a REPTEM survey flown in 2008 that
defines the base of the Narlaby Palaeochannel
· Downhole geophysics from historical uranium focused drilling has been
digitised, interpreted and wireframes developed
· 233 samples from 13 drillholes from south and north of Boland are at
the laboratory. These results will validate and refine the model with the aim
of supporting a near term maiden mineral resource estimation
Next Steps:
· Samples are being prepared for mineralogy studies to understand the
adsorption characteristics of REEs
· Sieve sizes are being assayed to understand distribution of REEs
· A total of 233 historic pulp samples from the greater Boland target
area have been submitted for re-analysis to validate the model of mineralised
geological formations
· A total of five holes were drilled, cased, and screened with slotted
PVC screens. Screens have been set at a depth to coincide with Zone 3
mineralisation. These wells will enable hydrology studies and support a future
pilot study
· Hydrology testing has commenced. Water quality and water yield data
will be compiled to define environmental baselines and evaluate productivity
potential
· Select zones of core have been sent to Australia's Nuclear Science
and Technology Organisation ("ANSTO") to enable column ISR testing. Results
from these tests are anticipated to support the amenability of mineralisation
to be mined through ISR
· Pregnant solutions from ANSTO testwork will be used by Watercycle
Technologies to advance a flow sheet through membrane desorption
· Hydrology testing has commenced. Water quality and water yield data
will be compiled to define environmental baselines and evaluate productivity
potential
Sonic Drilling - Overview of Boland Strategy
Results are from a five drillhole programme totalling 145m completed in
February 2024. The programme has successfully provided quality drill core that
is enabling Cobra to advance the ISR potential of the Boland ionic REE
discovery. Drilling was undertaken in a five-hole ISR wellfield configuration
at 25m spacings, where holes were cased and screened to support a future
"push-pull" pilot ISR study.
The wellfield was drilled proximal to Aircore hole CBAC00163 that yielded the
following intersections:
· Zone 1: 3m at 559 ppm TREO (24% MREO) from 18m (playa clay)
· Zone 2: 3m at 618 ppm TREO (22% MREO) from 21m (playa clay)
· Zone 3: 3m at 468 ppm TREO (21% MREO) from 27m (basal clay)
· Saprolite: 12m at 1,191 ppm TREO (27% MREO) from 36m
Cobra believed that, owing to the geological and chemical conditions that
promote ionic adsorption, higher grades would be defined concentrated to
lithologies with high permeability and be amenable to ISR.
Sonic drilling has enabled representative sampling. Narrow intervals relating
to geology from three holes were sampled and submitted for assay to evaluate
potential grade concentration. Length weighted average composites from three
sonic core holes assayed proximal to CBAC00163 validate grade concentration,
where:
o Zone 1: 3.1m at 1,007 ppm TREO (23.4% MREO) from 15.6m represents a 180%
increase in grade
o Zone 2: 1.9m at 1,043 ppm TREO (22% MREO) from ~20.5m represents a 169%
increase in grade
o Zone 3: 0.6m at 1,538 ppm TREO (MREO 23%, HREO 28%) from ~26.6m represents
a 329% increase in grade
Increased grades confined to permeable lithology is important from an ISR
standpoint and bodes well for future extraction success. Mineralised intervals
from the two holes not reported have been sent to ANSTO for bench scale leach
ISR testing. A summary of significant intersections is tabulated below:
Table 1: Significant intersections from sonic core holes
Mineralisation zone Hole ID From (m) To (m) Int (m) TREO Pr(6)O(11) Nd(2)O(3) Tb(2)O(3) Dy(2)O(3) MREO % HREO%
Zone 1 CBSC0001 15.6 19.2 3.7 1,025 49 172 4 22 24% 17%
Zone 2 CBSC0001 20.8 23.0 2.2 1,010 46 156 4 20 22% 18%
Zone 3 CBSC0001 27.0 27.7 0.7 2,118 90 321 10 59 23% 26%
Zone 1 CBSC0005 15.6 18.5 2.9 915 44 154 3 18 24% 16%
Zone 2 CBSC0005 19.5 21.4 1.9 1,226 56 192 4 19 22% 15%
Zone 3 CBSC0005 26.3 27.0 0.7 1,248 56 202 6 35 24% 27%
Zone 1 CBSC0004 15.7 18.5 2.8 1,082 48 167 4 20 22% 15%
Zone 2 CBSC0004 21.4 23.0 1.6 870 36 126 3 17 21% 17%
Zone 3 CBSC0004 26.3 26.8 0.5 1,130 45 179 7 38 24% 31%
Figure 1: Aerial photograph of the Boland wellfield with significant
intersections
Table 2: Length weighted averages of significant intersections
Mineralisation zone Int (m) TREO Pr(6)O(11) Nd(2)O(3) Tb(2)O(3) Dy(2)O(3) MREO % HREO%
Zone 1 3.1 1,008 47 165 4 20 23% 16%
Zone 2 1.9 1,042 46 159 3.4 19 22% 17%
Zone 3 0.6 1,538 66 240 8 45 23% 28%
Association of Metallurgy to Mineralised Lithology
Sonic core drilling has enabled the Company to evaluate the nature of
mineralisation and its potential to be mined via ISR. Whilst sizing results,
further assays, and bench scale ISR column leach tests are outstanding,
preliminary observations are very positive and correlate well to diagnostic
metallurgical tests performed by ANSTO. Observations and average recoveries by
zone are summarised in table 3:
Table 3: 2023 averaged metallurgical recoveries of magnet rare earths achieved
in ANSTO sighter testwork according to mineralised palaeochannel horizon and
the ranked ISR recovery potential
Min Zone Lith Summary Acidity (pH) Pr Nd Tb Dy Acid consumption (kg/t)
Zone 1 Upper playa clay 4 16% 20% 31% 33% 15.9
3 22% 26% 31% 40% 22.3
Zone 2 Middle playa clay and sand interbeds 4 22% 25% 37% 41% 17.3
3 36% 40% 52% 54% 28.8
Zone 3 Organic rich - clayey sand 4 35% 45% 44% 49% 9.4
3 47% 60% 79% 67% 17.6
Upper Saprolite Weathered granite 4 8% 11% 21% 16% 10.9
3 9% 13% 27% 25% 29.2
Downhole Geophysics and Implications for Scalability
All sonic core holes were logged for lithology and compared against downhole
geophysical measurements. Downhole geophysical responses can de directly
attributed to the geological formations that host mineralisation. In
particular:
· Zone 1: mineralisation is confined between two distinct gamma peaks
at the margins of the mineralised unit, where the lower peak relates to a
narrow, coarse reduced sand unit
· Zone 2: mineralisation has an overall low gamma response where small
spikes associate with elevated REE grades
· Zone 3: mineralisation is associated with a high geophysical response
that is interpreted to be a product of the high quantity of organics contained
within the mineralised sandy clay
Figure 2-4: Grade distribution of rare earths down-hole and their association
to palaeochannel geology and associated downhole geophysics
Drillhole: CBSC0001 Drillhole: CBSC0004
Drillhole: CBSC0005
· Downhole geophysics across all five sonic core holes exhibit
responses that can be attributed to mineralised lithologies
· The Boland prospect is located on EL5953 "Minipa" where uranium
explorers have previously undertaken exploration and carried out downhole
geophysics on numerous holes across the tenement
· Downhole geophysical data and historical logs have been digitised and
interpreted, enabling Cobra's technical team to assess the extent of the
mineralised zones across the tenement area
· Mineralised zones are most prominent on the margins of the
palaeosystem, which is interpreted to be a result of their marine
transgressional deposition and not the fluvial depositional environment that
is constrained in the central portions of the palaeochannel
· This supports significant scale potential as sediments from marine
transgression are interpreted to be more extensive across the palaeosystem
· The scale of the geological formations that host mineralisation are
mapped across ~155km(2) on EL5953 alone. Recent reanalysis results demonstrate
that these formations host mineralisation across the Company's greater
tenement holdings which cover an additional 1,850km(2) of palaeosystems
· Re-analysis of samples from drillholes highlighted in Figure 5 are
aimed to validate the modelled zones and confirm estimated volumes
· Collation and digitisation of downhole geophysical data across
Cobra's greater land tenure is ongoing and will inform further re-analysis and
future drilling
· Follow-up Aircore drilling will be designed to infill shortfalls in
geological data, supporting a maiden mineral resource estimate
Figure 5: 3D section highlighting the modelled geological units that host REE
mineralisation (zones 1-3)
Figure 6: Plan view - highlighting the regional scale of the mapped geological
units that host Boland ionic REE mineralisation and the holes that form stage
2 of the Company's re-assay strategy
Particle Size Distribution
Samples from each mineralised zone were taken and screened to evaluate:
· The particle distribution of mineralised lithologies
· The distribution of grade to particle size
· The permeability of material and its amenability to ISR
Samples were wet screened, and only the results on a zone 3 sample are
reported. Results are highly favourable for ISR and indicate:
· Zone 3 mineralisation has a high quantity of sand with 67% of the
sample mass screening above 0.1mm
· Particle size distribution parameters have been used to calculate the
potential permeability using the Kozeny-Carman equation1, where:
o Using the median particle size distribution yields a very high
permeability of 275 m/day
o Using the lower quartile of the particle distribution analysis provides a
moderate -high permeability of 135 m/day
Figure 7: Particle size distribution of zone 3 (27-27.5m) from drillhole
CBSC0001
Figure 8: Cumulative distribution of particle sizes by screen passing
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.
About Cobra
Cobra is defining a unique multi-mineral resource at the Wudinna Gold and Rare
Earth Project in South Australia's Gawler Craton, a tier one mining and
exploration jurisdiction which hosts several world-class mines. Cobra's
Wudinna tenements totalling 1,832 km(2), and other nearby tenement rights
totalling 2,941 km(2), contain highly desirable and ionic rare earth
mineralisation, amenable to low-cost, low impact in situ recovery mining, and
critical to global decarbonisation. Additionally, Cobra holds a 213 km(2)
exploration tenement in northern Tasmania which is also considered highly
prospective for ionic rare earth mineralisation.
Cobra's Wudinna tenements also contain extensive orogenic gold mineralisation
and are characterised by potentially open-pitable, high-grade gold
intersections, with ready access to infrastructure. Cobra has 22 orogenic gold
targets outside of the current 279,000 Oz gold JORC Mineral Resource Estimate,
and several iron oxide copper gold (IOCG) targets.
Follow us on social media:
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(https://www.linkedin.com/company/cobraresourcesplc)
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(https://twitter.com/Cobra_Resources)
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Appendix 1: JORC Code, 2012 Edition - Table 1
Section 1 Sampling Techniques and Data
Criteria JORC Code explanation Commentary
Sampling techniques · Nature and quality of sampling (eg cut channels, random chips, or 2023
specific specialised industry standard measurement tools appropriate to the
minerals under investigation, such as down hole gamma sondes, or handheld XRF RC
instruments, etc). These examples should not be taken as limiting the broad
meaning of sampling. · Samples were collected via a Metzke cone splitter mounted to the
cyclone. 1m samples were managed through chute and butterfly valve to produce
· Include reference to measures taken to ensure sample representivity a 2-4 kg sample. Samples were taken from the point of collar, but only samples
and the appropriate calibration of any measurement tools or systems used. from the commencement of saprolite were selected for analysis.
· Aspects of the determination of mineralisation that are Material to · Samples submitted to Bureau Veritas Laboratories, Adelaide, and
the Public Report. pulverised to produce the 50 g fire assay charge and 4 acid digest sample.
· 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 AC
assay'). In other cases more explanation may be required, such as where there
is coarse gold that has inherent sampling problems. Unusual commodities or · A combination of 2m and 3 m samples were collected in green bags
mineralisation types (eg submarine nodules) may warrant disclosure of detailed via a rig mounted cyclone. An PVC spear was used to collect a 2-4 kg sub
information. sample from each green bag. Samples were taken from the point of collar.
· Samples submitted to Bureau Veritas Laboratories, Adelaide, and
pulverised to produce the 50 g fire assay charge and 4 acid digest sample.
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.
· Samples have been submitted to Bureau Veritas for 4 acid digest
ICP analysis.
Drilling techniques · Drill type (eg core, reverse circulation, open-hole hammer, rotary 2023
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, · Drilling completed by Bullion Drilling Pty Ltd using 5 ¾"
whether core is oriented and if so, by what method, etc). reverse circulation drilling techniques from a Schramm T685WS rig with an
auxiliary compressor.
· Drilling completed by McLeod Drilling Pty Ltd using 75.7 mm NQ
air core drilling techniques from an ALMET Aircore rig mounted on a Toyota
Landcruiser 6x6 and a 200psi, 400cfm Sullair compressor.
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 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 Aircore & RC
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 · All drill samples were logged by an experienced geologist at the
costean, channel, etc) photography. time of drilling. Lithology, colour, weathering and moisture were documented.
· The total length and percentage of the relevant intersections logged. · Logging is generally qualitative in nature.
· All drill metres have been geologically logged on sample
intervals (1-3 m).
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 2021-onward
taken.
· The use of an aluminum scoop or PVC spear to collect the required
· If non-core, whether riffled, tube sampled, rotary split, etc and 2-4 kg of sub-sample from each AC sample length controlled the sample volume
whether sampled wet or dry. submitted to the laboratory.
· For all sample types, the nature, quality and appropriateness of the · Additional sub-sampling was performed through the preparation and
sample preparation technique. processing of samples according to the lab internal protocols.
· Quality control procedures adopted for all sub-sampling stages to · Duplicate AC samples were collected from the green bags using an
maximise representivity of samples. aluminium scoop or PVC spear at a 1 in 25 sample frequency.
· Measures taken to ensure that the sampling is representative of the · Sample sizes were appropriate for the material being sampled.
in situ material collected, including for instance results for field
duplicate/second-half sampling. · Assessment of duplicate results indicated this sub-sample method
provided good repeatability for rare earth elements.
· Whether sample sizes are appropriate to the grain size of the
material being sampled. · RC drill samples were sub-sampled using a cyclone rig mounted
splitter with recoveries monitored using a field spring scale.
· Manual re-splitting of RC samples through a riffle splitter was
undertaken where sample sizes exceeded 4 kg.
· RC field duplicate samples were taken nominally every 1 in 25
samples. These samples showed good repeatability for REE.
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 · Samples were submitted to Bureau Veritas Laboratories, Adelaide
laboratory procedures used and whether the technique is considered partial or for preparation and analysis.
total.
· Multi element geochemistry were digested by four acid ICP-MS and
· For geophysical tools, spectrometers, handheld XRF instruments, etc, analysed for Ag, Ce, Cu, Dy, Er, Eu, Gd, Ho, La, Lu, Mg, Na, Nd, P, Pr, Sc,
the parameters used in determining the analysis including instrument make and Sm, Tb, Th, Tm, U, Y and Yb.
model, reading times, calibrations factors applied and their derivation, etc.
· For the sonic samples Ag was removed from the analytical suite
· Nature of quality control procedures adopted (eg standards, blanks, and V was included
duplicates, external laboratory checks) and whether acceptable levels of
accuracy (ie lack of bias) and precision have been established. · Field gold blanks and rare earth standards were submitted at a
frequency of 1 in 25 samples.
· Field duplicate samples were submitted at a frequency of 1 in 25
samples
· Reported assays are to acceptable levels of accuracy and
precision.
· Internal laboratory blanks, standards and repeats for rare earths
indicated acceptable assay accuracy.
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 · RC drillholes have been drilled between -60 and -75 degrees at
possible structures and the extent to which this is known, considering the orientations interpreted to appropriately intersect gold mineralisation
deposit type.
· Aircore and Sonic drill holes are vertical.
· 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. Pre 2021
· Company staff collected or supervised the collection of all
laboratory samples. Samples were transported by a local freight contractor
· No suspicion of historic samples being tampered with at any stage.
· Pulp samples were collected from Challenger Geological Services and
submitted to Intertek Genalysis by Cobra Resources' employees.
2021-onward
· 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.
· 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 2: 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 relevant Native Title
party.
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 REDOX 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
(pH3)
· Ionic REE mineralisation occurs in reduced clay intervals that
contact both saprolite and permeable sand units. Mineralisation contains
variable sand quantities that is expected
Drillhole Information · A summary of all information material to the understanding of the · Exploration results are not being reported as part of the Mineral
exploration results including a tabulation of the following information for Resource area.
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.
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)
· 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 · Most intercepts are vertical and reflect true width intercepts.
Exploration Results.
· Exploration results are not being reported for the Mineral Resource
· If the geometry of the mineralisation with respect to the drill hole area.
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').
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 · Samples have been submitted for pressurized column leach testing to
extensions or depth extensions or large-scale step-out drilling). confirm the ISR potential.
· Diagrams clearly highlighting the areas of possible extensions, · Hydrology, permeability and mineralogy studies will be performed on
including the main geological interpretations and future drilling areas, core samples.
provided this information is not commercially sensitive.
· Installed wells will be used to capture baseline hydrology data and
shall be utilized for a future pilot study.
· 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)
· 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').
· Most intercepts 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.
· Samples have been submitted for pressurized column leach testing to
confirm the ISR potential.
· Hydrology, permeability and mineralogy studies will be performed on
core samples.
· Installed wells will be used to capture baseline hydrology data and
shall be utilized for a future pilot study.
Appendix 1: 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
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