Maiden Ore Reserve positions Koppamurra for development
Released
Released
Announcement PDF
ASX: AR3 | MARKET ANNOUNCEMENT ASX Release: 25 June 2026
Maiden Ore Reserve positions Koppamurra for
development
Maiden Ore Reserve and updated Mineral Resource estimates for Koppamurra
Highlights
Maiden Ore Reserve Established Development Path
• Maiden Ore Reserve of 26 Mt at 920ppm Total Rare Earth Oxide (TREO) marks Koppamurra's
most significant de-risking milestone and underpins potential mine planning, financing and
development.
• Ore Reserve grade is ~22% higher than the global Mineral Resource average grade of 751
ppm TREO, highlighting the optionality for mine sequencing across a large, regionally extensive
orebody.
• 48% of the rare earth basket comprises high-value heavy and magnet rare earths, critical to
EVs, wind turbines and defence applications.
Mineral Resource Strengthened
• Updated Mineral Resource of 243 Mt at 751 ppm TREO, reinforcing Koppamurra’s scale and
quality.
• Resource increased by ~7 Mt versus September 2024, with a modest grade improvement on no
additional drilling.
• Refined geological modelling and resource interpretation, together with expanded reporting of
individual rare earth elements.
Significant Growth Potential
• UpdatedExploration Target across the northern andsouthernprojectareas highlight substantial
potential for future resource growth and expansion.
AR3 Managing Director and CEO, Travis Beinke said:
"China's export controls on rare earths have fundamentally changed the economics of what we are building at
Koppamurra. Western supply chains need alternatives — and they need them now. Today's maiden Ore Reserve,
delivered alongside our Pre-Feasibility Study, confirms that Koppamurra can be one of them.
Twenty-six million tonnes at 920 ppm TREO, with a basket heavily weighted toward the magnet and heavy rare
earths the world is scrambling to source outside China — that is a compelling proposition. Backed by Australian
Government grant funding, a simple low-capital processing pathway and five years of rigorous technical
development, AR3 is positioned to move quickly."
Major development milestone
AustralianRareEarths(ASX:AR3)hasachievedamajormilestonewiththeestablishmentofamaidenOreReserve
fortheKoppamurraProject.
The 26 Mt at 920 ppm TREO Probable Ore Reserve has been converted directly from Measured and Indicated
Mineral Resources and provides a well-defined starting point for a development that AR3 has designed to be
scalable — with staged satellite development opportunities supported by a global resource of 243 Mt and
significantexplorationupsidehighlightedbytheExplorationTargetreportedinthisannouncement.
Updated Mineral Resource Estimate
AR3ispleasedtoprovideanupdatedMineralResourceestimatefortheKoppamurraProject.Whilenoadditional
drillinghas beencompletedsince theSeptember2024MineralResourceestimate, the update reflectsimproved
geological modelling and resource interpretation, together with expanded reporting of individual rare earth
elementsusingtheexistingdrillingdataset(SeeAppendix2).
AkeyoutcomeoftheMineralResourceupdateistheimprovedgeologicalmodel,whichhasre-domainedtheionic
clay-hosted mineralisation to more accurately define the principal REE-bearing zone and isolate calcium-rich
materialassociatedwithlimestonecontactsandweatheredlimestoneclasts.TheadditionofZones4and5(Figure
1) has materially improved the representation of calcium distribution across the resource model, reducing the
averagecalciumcontentwithintheprincipalREE-bearingdomain,Zone3,toapproximately3.5%,comparedwith
approximately5%inthepreviousMineralResourceestimate.
Figure1–TypesectionN5878400showingmodelzonesanddrillholes,with10xverticalexaggeration.Zones4and5were
addedtobetterconstrainmineralisationandcalciumdistribution.
The JORC classification for the Koppamurra Mineral Resource has been assigned in accordance with the JORC
Code (2012), based on geological confidence, drill-hole spacing, sample support within domains, domain
continuityandvariography.Classificationisindependentofeconomicassumptions.
Drill spacings tosatisfy the Inferred, Indicated and Measured JORCResource Categories are set at 240m, 120 m
and60m,respectively.DrillingthatinformstheExplorationTargetwasconductedatlinespacingsofatleast1km,
andinsomeareas,upto2kmapart,withdrillholespacingsalongthelinestypicallyrangingfrom100mto400m.
Grade estimation was undertaken using Kriging, informed by domain-specific variography and control
strings aligned to the observed geological trend. Inverse Distance estimation was used as a check
method, with results comparable to the Kriged estimates. Conservative grade capping was applied to
the upper tail of the grade distributions to limit the influence of isolated high-grade samples. Validation
of the block model included on-screen visual inspection in section and plan, drill hole versus model
statistical comparisons, trend analysis by easting, northing and down-hole direction, cut-off sensitivity
analysis, and qualitative plan-view heat maps. These checks indicate that the block model provides a
reasonable and representative estimate of grade distribution and continuity at the current level of
drilling.
This latest density work completed by AR3 used a Formation Density Probe to determine in-situ wet
density values down hole, which was then refined using a Neutron Porosity Probe to determine water
content. Of the 37 aircore drill holes used for the density test work, 14 of them (totalling 111 m) were
also sampled at 0.5 m intervals to be used as reference data for the correlate the Neutron Porosity
Probe data to in-situ moisture percentage.
The updated Global Mineral Resource estimate for the Koppamurra Project using a cut-off grade of 325
ppm TREO-CeO₂ is 243 Mt at 751 ppm TREO and 493 ppm TREO-CeO₂ (Table 1 & Figures 2/3). The
Mineral Resource comprises Measured, Indicated and Inferred categories, with Zone 3 accounting for
approximately 95% of the reported tonnage and remaining the primary REE-bearing domain.
This updated Mineral Resource represents an overall increase of ~7.0 Mt to the global resource and
slight increase to the grade up to 751ppm from 748 TREO.
The updated Mineral Resource estimate has been expanded to report the full suite of rare earth elements. This
enhanced reporting provides a more comprehensive representation of the mineralisation and highlights the
potentialvaluecontributionofadditionalindividualrareearthelementswithintheKoppamurraProject.
Table1–KoppamurraMRE2026fullelementsuite.Roundingmaycausedifferencesinthelastsignificantfigure.
Mineral
Resource
Category
Tonnes BD TREO TREO-
CeO2
MREO La2O3 CeO2 Pr6O11 Nd2O3 Sm2O3 Gd2O3
Mt gcm3 ppm ppm %TREO ppm ppm ppm ppm ppm ppm
Measured 0.9 1.6 773 502 25.1 125 271 36 135 27 25
Indicated 113 1.6 766 502 25.3 121 264 35 135 27 26
Inferred 130 1.6 737 486 25.3 121 251 34 130 26 24
Grand Total 243 1.6 751 493 25.3 121 257 35 132 26 25
Summary of Global Mineral Resources continued
Mineral
Resource
Category
Tb4O7 Dy2O3 Ho2O3 Er2O3 Eu2O3 Tm2O3 Yb2O3 Lu2O3 Y2O3 U3O8 ThO2
ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm
Measured 4 20 4 10 6 1 8 1 102 1 21
Indicated 4 20 4 10 6 1 8 1 106 2 19
Inferred 3 19 4 9 6 1 7 1 102 2 18
Grand Total 4 19 4 10 6 1 8 1 104 2 19
Figure2–JORCKoppamurraMineralResourceareasandCategories.Inferredresourcecategoriesdefinedinthenorthern
ExplorationTargetiswhereinfilldrillingwasconductedhighlightingthepotentialforfurtherresourcegrowth.
Figure3-JORCMineralResourceCategoriesfortheSouthernKoppamurraResourceArea.
Updated Exploration Target
While no additional drilling has been completed since the September 2024 Exploration Target, the
update reflects improved geological modelling and resource interpretation using the existing drilling
dataset (See Appendix 2).
The Koppamurra project includes a significant Exploration Target across both the southern and
northern extents of the project region. The Exploration Target is shown in Figures 2 & 3 for the northern
and southern extents respectively and highlights the size of the overall project and its potential for
further definition.
The updated Exploration Target now ranges 680 Mt at 820ppm TREO to 3620 Mt at 540 ppm TREO. The
potential quantity and grade of the Exploration Target is conceptual in nature, as there has been
insufficient exploration undertaken to estimate a Mineral Resource and it is uncertain if further
exploration will result in the estimation of a Mineral Resource.
The updated 2026 Exploration Target estimate is set out in Table 2 below and Figures 2 & 3. Exploration
Target has been reported using a cut-off grade range of 225 ppm and 425 ppm TREO-CeO2.
Table 2– Koppamurra Exploration Target 2026. Rounding may cause differences in the last significant
figure.
Material Type
Exploration
Target
Zone Material BD TREO TREO-
CeO2
MREO Dy2O3 Tb4O7 Nd2O3 Pr6O11
Mt gcm3 ppm ppm ppm ppm ppm ppm ppm
Exploration
Target
3 650 - 3120 1.6 560 -820 360 - 540 140 - 210 15 - 20 3 - 4 100 - 150 25 - 40
4 30 - 500 1.6 420 - 690 300 - 500 110 - 190 10 - 20 2 - 3 80 - 140 20 - 40
Total 680 - 3620 1.6 540 – 820 350 - 540 140 - 210 15 - 20 3 - 4 100 - 150 25 - 40
Over the next 2 years, AR3 expects to undertake further drilling across priority areas of the defined
Exploration Target. The program is intended to progressively test geological continuity and reduce drill
spacing from the current wide-spaced pattern to approximately 240 m and, where warranted, 120 m,
providing additional data that may support future Mineral Resource estimation.
The updated Mineral Resource and Exploration Target model demonstrates a significant improvement
in geological understanding of the Koppamurra deposit. The incorporation of additional mineralisation
domains, enhanced calcium modelling and reporting of a broader suite of rare earth elements has
resulted in increased resource tonnage and grade, a substantial reduction in calcium content within
the ore zone 3, and a more robust Mineral Resource estimate which underpins the Ore Reserve.
Ore Reserve Estimation
The Maiden Ore Reserve estimate for the Koppmurra Deposit is 26Mt at 920ppm TREO as of 25 June
2026 (Table 3). Tonnages and grades are rounded as appropriate and mineral assemblage is reported
as parts per million. Measured and Indicated Mineral Resources have been converted to Probable Ore
Reserves only. Ore Reserves are a subset of Mineral Resources and are reported in accordance with
the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (The
Joint Ore Reserves Committee Code – JORC 2012 Edition).
Table 3 Ore Reserve Estimate as at 25 June 2026. Roundingmaycausedifferencesinthelastsignificant
figure.
Category
Material
(Mt)
BD
(g/cm³)
TREO
(ppm)
TREO-
CeO2
(ppm)
La2O3
(ppm)
CeO2
(ppm)
Pr6O11
(ppm)
Nd2O3
(ppm)
Sm2O3
(ppm)
Gd2O3
(ppm)
Probable 26 1.6 920 602 141 324 43 167 33 32
OreReserveEstimationContinued.
Category
Tb4O7
(ppm)
Dy2O3
(ppm)
Ho2O3
(ppm)
Er2O3
(ppm)
Eu2O3
(ppm)
Tm2O3
(ppm)
Yb2O3
(ppm)
Lu2O3
(ppm)
Y2O3
(ppm)
U3O8
(ppm)
ThO2
(ppm)
Probable 4.5 25 4.7 13 7.6 1.6 10 1.4 125 1.4 19
To develop the Ore Reserve estimate the cost, recovery, and price parameters (Modifying Factors) were
input to the resource model using Datamine software and applied to Measured, Indicated and Inferred
resource cells. The area included for the Ore Reserve estimate includes the proposed ML outline, and
the area to the immediate east, west, and south of the proposed ML application area. The northern
areas were excluded from the Ore Reserve estimate.
For the purposes of this optimisation process, a global mining recovery of 95% was applied to the
resource model during the economic evaluation. Inferred resource cells were included in the
optimisation process but were excluded from the final Ore Reserve estimation. The resultant cash
value for each resource model cell was then derived. The model was optimised using the MaxiPit
software and a pit shells generated. The most optimal and economic pit shell was selected for the
ultimate pit shell design.
The PFS for the Koppamurra Project (see ASX 25 June 2026) is considered to provide appropriate
support and good degree of confidence in the Modifying Factors used in this Ore Reserve estimation,
which are all derived from the PFS.
Consequently, the Ore Reserve classification primarily follows the Mineral Resource estimate
classification, and material classified as Measured and Indicated in the Mineral Resource estimate is
classified as Probable. Material classified as Inferred has been reported separately as a Production
Target and not included in the Ore Reserve estimate.
A number of Modifying Factors required to support the Ore Reserve estimate remain subject to ongoing
studies, approvals, and detailed design activities. These include the finalisation of permitting and
regulatory approvals, completion of detailed engineering and mine design, refinement of operating and
capital cost estimates, and confirmation of certain environmental, geotechnical, hydrogeological,
infrastructure, and marketing assumptions.
These activities are currently being progressed as part of the ongoing project development process,
have been documented and detailed in the supporting PFS document and are considered typical for a
project at this stage of evaluation. Based on the studies completed to date, there are no identified fatal
flaws, material impediments, or technical issues that would reasonably be expected to prevent the
granting of the necessary approvals or the implementation of the proposed mining operation. The
Competent Person considers that the remaining activities and approvals can be addressed within
normal project development timeframes and that there is a reasonable basis to apply the relevant
Modifying Factors in support of the Ore Reserve estimate.
Figure 5- Proposed mining sequence by year for the Koppamurra Deposit. Note the pits designed within
Inferred Resource have not been included in the 26Mt Ore Reserve.
The maiden Ore Reserve represents a major step forward for the Koppamurra Project and provides a
strong platform for development and reinforces AR3’s confidence in the project’s scale, quality and
long-term growth potential.
Information provided pursuant to ASX Listing Rule 5.8.1
Geology and Geological Interpretation
The Koppamurra Project is located within the Murray Basin of south-eastern Australia, along the
eastern margin of the Kanawinka Escarpment within South Australia’s Limestone Coast region,
extending into western Victoria. The Project hosts shallow clay-hosted rare earth mineralisation
developed within weathered Pleistocene lacustrine sedimentary clay unit and associated clay-rich
sediments overlying Gambier Limestone, a regionally extensive carbonate unit of the Murray Group.
The geological setting reflects a complex history of marine incursions, coastal sedimentation, tectonic
uplift and prolonged weathering associated with development of the Padthaway High and Kanawinka
Fault system, which controlled preservation and enrichment of the REE-bearing clay horizons. Rare
earth mineralisation occurs within shallow ionic adsorption clay zones typically developed within 2–3
metres above the highly weathered limestone basement. The mineralised profile generally comprises
thin sandy overburden overlying REE-enriched smectite-rich clay horizons with strong lateral continuity
across the Project area. Research completed by AR3 and independent academic groups indicates the
Koppamurra mineralisation represents an unusual sediment-hosted ionic clay rare earth system
formed through weathering, sedimentary transport and geochemical enrichment processes linked to
far-field granitic source rocks of the Lachlan Orogen.
Drilling, Sampling, and analytical
Drilling, sampling, analytical and quality assurance procedures remain consistent with those
previously reported by the Company. No material changes have occurred to the underlying drilling
database, sampling methodology, assay procedures or QA/QC protocols used to support the updated
Mineral Resource Estimate. Details of these procedures are provided in the Company's previous
Mineral Resource announcements and accompanying JORC Table 1 disclosures.
Estimation methodology
Mineral Resource
The JORC Mineral Resource Classification for the Koppamurra project deposit was supported by drill
hole spacing, geological continuity and variography of TREO, TREO-CeO2 of the target mineralised
domain Zone 3 and 4.
TheclassificationofMeasured,IndicatedandInferredMineralResourceswassupportedbyallthecriteria
noted above. A significant Exploration Target has also been defined which can be used to determine
areas of significant prospectivity for future drill programmes.
As a Competent Person, Mineral Technologies – Head of Geology & Mining Greg Jones considers that
the results of the Mineral Resource estimate appropriately reflects a reasonable view of the deposit
categorisation and reasonable prospects of eventual economic extraction (RPEEE).
Ore Reserve
The OPEX cost, recovery and price parameters (Modifying Factors) were applied to the resource model
using Datamine software and applied to all Measured, Indicated and Inferred resource cells.
The resultant net cash value for each resource model cell was then derived. This cash value model was
optimised using software that uses the industry standard Lerch-Grossman (LG) algorithm to generate
a series of nested pit shells. The optimisation process was repeated at 5% increments (from 50% to
150% of the base case of Modifying Factors) to revenue (while maintaining the same cost) and new pit
shell derived. The purpose of doing this is to generate a series of both incrementally smaller, higher-
grade pit-shells (of increments less than 100% base case) and larger, lower grade pit-shells (of
increments greater than 100% base case). These pit-shells were each assessed to identify which
supported the project’s objectives on acceptable mine life, EBITDA and return on capital.
Cut-off grades, including basis for the selected Cut-off Grade
Mineral Resource
The selection of the 325ppm TREO-CeO2 cut-off grade used for reporting was based on the experience
of the Competent Person and given the early stage of the Koppamurra project, this cut-off grade was
selected based on a peer review of publicly available information from more advanced projects with
comparable mineralisation styles (i.e., clay-hosted rare earth mineralisation) and comparable
conceptual processing methods. Material above this cut-off generates a grade of over 700 ppm TREO,
and in the opinion of the Competent Person meets the conditions for reporting of a Mineral Resource
with reasonable prospects of eventual economic extraction.
Ore Reserve
The cash value model was optimised using software that uses the industry standard Lerch-Grossman
algorithm to generate a series of nested pit shells. This estimation methodology is a much more
rigorous method of determining pit limits than using cut-off grades, and therefore cut-off grades have
not been used. The net cash value calculated for each model cell was used to drive the LG algorithm
and from thence, the most representative and economic pit shell was selected and used for the
ultimate pit design.
Mining and metallurgical methods / material Modifying Factors
Mineral Resource
No specific mining or metallurgical methods or parameters were incorporated into the modelling
process. Representative material from the current drilling programme will be utilised in ongoing
metallurgical testwork.
Ore Reserve
Mineral Resources are converted to Ore Reserves by open pit optimisation software (Datamine MaxiPit)
to provide a guide for detailed design and scheduling. The Modifying Factors applied were based on
work conducted during the PFS, including metallurgical test work, development of prices for products,
and operating cost development to support the proposed mining and processing operations. A subset
of the shells were reviewed to test production profiles, final production requirements, and financial
investment decisions. The preferred pit shell (Revenue Factor 100% or Base Case) was selected for
more detailed mine planning and scheduling of ore and overburden.
The announcement has been authorised for release by the Board of Australian Rare Earths Limited.
For further information please contact:
Australian Rare Earths Limited IR & Media Enquiries
Travis Beinke Jessica Fertig
Managing Director and CEO Tau Media
T: 1 300 646 100 E: jessica@taumedia.com.au
Competent Person’s Statement
The information in this report which relates to Mineral Resources and Exploration Target for the
Koppamurra rare earth deposit is based upon and fairly represents information compiled by Mr. Greg
Jones who is a Fellow of the Australasian Institute of Mining and Metallurgy. Mr. Jones is a full-time
employee of Mineral Technologies and has sufficient experience relevant to the style of mineralisation,
the type of deposit under consideration and to the activity which he is undertaking 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. Jones consents to the inclusion in this report of the
matters based on his information in the form and context in which it appears.
The information in this report which relates to Ore Reserve for the Koppamurra rare earth deposit is
based upon and fairly represents information compiled by Mr. Chris Sykes who is a Qualified
Professional of the Mining and Metallurgical Society of America (MMSA) and has sufficient experience
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. Sykes consents to the inclusion in
this report of the matters based on his information in the form and context in which it appears.
The Ore Reserve quoted in this report is based on information supplied by AR3 Limited and compiled
by Mr. Chris Sykes. At the time of preparation of this estimate Mr. Sykes is employed by Mineral
Technologies.
Forward Looking Statement
This announcement contains forward-looking statements which involve a number of risks and
uncertainties. These forward-looking statements are expressed in good faith and believed to have a
reasonable basis. These statements reflect current expectations, intentions or strategies regarding the
future and assumptions based on currently available information. Should one or more of the risks or
uncertainties materialise, or should underlying assumptions prove incorrect, actual results may vary
from the expectations, intentions and strategies described in this announcement. No obligation is
assumed to update forward looking statements if these beliefs, opinions, and estimates should change
or to reflect other future developments.
Appendix 1- JORC Tables
Appendix 2- List of Collars
Appendix 3- List of Significant Intersections- (Southern Resource Area)
Appendix 4- List of Significant Intersections- (Northern Resource and E.T. Area)
JORC Table 1
Section 1 Sampling Techniques and Data
Criteria Explanation Comment
Sampling
techniques
Nature and quality of sampling
(e.g., cut channels, random chips,
or specific specialised industry
standard measurement tools
appropriate to the minerals under
investigation, such as down hole
gamma sondes,orhandheld 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
appropriatecalibration 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
(e.g., ‘reverse circulation drilling
was used to obtain 1 m samples
from which 3 kg was pulverised to
produce a 30 g charge for fire
assay’). In other cases, more
explanation may be required, such
as where there is coarse gold that
has inherent sampling problems.
Unusual commodities or
mineralisation types (e.g.,
submarine nodules) may warrant
disclosure
of detailed information.
RC Aircore drilling methods were used obtain samples from the
October-December 2021, February-April 2022, September-
December 2022 February- June 2023, and October-December
2023 drilling programs.
Aircore drilling (1 m intervals) used for gradeinterpolation; push-
core and auger used for geology only.
The following information covers the sampling process:
All air core samples were collected from the rotary splitter
mounted at the bottom of the cyclone using a pre-numbered
calico bag and plastic UV sample bag. The samples were
geologically logged at 1 m intervals using the marked calico
sample which averaged ~1.5 kg in mass.
A handheld Olympus Vanta XFR Analyser was used to assess the
geochemistry of the air core samples in the field. The XRF
analysis provided a full suite of mineral elements for
characterising the lithological units.
XRF readings were downloaded from the XRF Analyser at the
end of each day and uploaded to the Australian Rare Earths
Azure Data Studio database.
1,137 field duplicate pairs collected and inserted blindly into
the sample batches (~1:30). Spearman correlation 0.911 (no
material bias).
At the laboratory, the samples were oven dried at 105 degrees
for a minimum of 24 hours and secondary crushed to 3 mm
fraction and then pulverised to 90% passing 75 µm. Excess residue
was maintained for storage while the rest of the sample placed in
8x4 packets and sent to the central weighing laboratory. The
samples were submitted for analysis using XRF-ICP-MS method.
Laboratory repeats inserted at ~1:20; Spearman correlation
0.999 across BV Perth and BV Adelaide.
Commercially obtained standards were inserted by the
laboratory at a rate of ~ 1 in 10 into the sample sequence.
Standards (OREAS101A/524) show results predominantly
within ±1SD; no drift observed.
Umpire comparison (BV Perth vs Adelaide) Spearman
correlation 0.9939; no bias detected.
Nominal values (lower 10th percentile by lithology) applied
prior to compositing to avoid grade smearing.
Drilling
techniques
Drill type (e.g., core, reverse
circulation, open- hole hammer,
rotary air blast, auger, Bangka,
sonic, etc) and details (e.g., 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).
Drilling was completed using a Mcleod or Wallis air ore drill rig
(Landcruiser 6x6 or similar) for the drilling.
Aircore drilling is a form of reverse circulation drilling where the
sample is collected at the face and returned inside the inner tube.
The drill cuttings are removed by injection of compressed air into
the hole via the annular area between the inner tube and the drill
rod.
Aircore drill rods used were 3 m long.
NQ diameter (76 mm) drill bits and rods were used.
All aircore drill holes were vertical with depths varying
between 2 m and 36 m.
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.
Drill sample recovery for aircore is monitored by recording
sample condition descriptions where ‘Poor’ to ‘Very Poor’ were
used to identify any samples recovered which were potentially
not representative of the interval drilled.
A comment was included where water injection was required to
recover the sample from a particular interval. The use of water
injection can potentially bias a sample and very little water
injection was required during this drilling program.
No significant loses of samples were observed due to the shallow
drilling depths (<36 m).
The rotary splitter was set to an approximate 20% split,
which produced approximately 1.5 kg sample for each
meter interval.
The 1.5 kg sample was collected in a pre- numbered calico
bags and the remaining 80% (5 kg to 8 kg) was collected in
plastic UV bags labelled with the hole number and sample
interval.
At the end of each drill rod, the drill string is cleaned by
blowing down with air to remove any clay and silt
potentially built up in the sample pipes and cyclone.
No relationship exists between sample recovery and grade.
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.
All aircore samples collected in calico bags were logged for
lithology, colour, cement type, hardness, percentage rock
estimate, sorting, and any relevant comments such as moisture,
sample condition, or vegetation.
Geological logging data for all drill holes was qualitatively
logged onto Microsoft Excel spreadsheet using a Panasonic
Toughbook with validation rules built into the spreadsheet
including specific drop- down menus for each variable. The
data was uploaded to the Australian Rare Earths Azure Data
Studio database.
Every drill hole was logged in full and logging was undertaken
with reference to a drilling template with codes prescribed and
guidance to ensure consistent and systematic data collection.
Sub-sampling
techniques and
sample
preparation
If core, whether cut or sawn and
whether quarter, half or all cores
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 allsub-
sampling stages to maximise
representivity of samples.
Measures taken
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