Niobium-Rare Earth Carbonatite System Identified at Overland
Released
Released
Announcement PDF
ASX: AR3 | MARKET ANNOUNCEMENT ASX Release: 8 July 2026
Discovery of Niobium-Rare Earth Carbonatite System
Identified at Overland Project
AR3 has identified a new niobium-rare earths mineral system at its 100%-owned Overland
Project, expanding the Company's critical minerals exposure beyond its existing Koppamurra
REE development and Overland uranium targets.
Highlights
• Drilling has identified a niobium–rare earth carbonatite-style mineral system at Overland; a discovery style
globally recognised as a major source of both REEs and niobium, both critical minerals with strong demand.
• Significant niobium–rare earth intersections returned from drill hole OV167, which intersected a 19-metre
interval of anomalous rare earth and niobium mineralisation from 86 metres to end of hole.
• The mineralised interval remains open at depth, with OV167 ending in anomalous basement-hosted rare earth
and niobium mineralisation.
• Significant intersection for OV167 - 19m @ 0.61% Total Rare Earth Oxides (TREO), with 20% of the TREO
Neodymium+Praseodymium oxides (NdPr) and 1.7% of the TREO Dysprosium+Terbium oxides (Dy Tb), including:
o 7m @ 0.56% TREO (20% NdPr & 2.3% Dy Tb), with 0.27% Nb2O5 from 86m
Including 1m @ 1.0% TREO with 0.53% Nb2O5 from 87m
o 3m @ 1.16% TREO (17% NdPr & 0.8% Dy Tb), from 93m
o 9m @ 0.46% TREO (22% NdPr & 1.7% Dy Tb), from 96m
Including 3m @ 0.57% TREO, from 97m
• The results define a significant new early-stage niobium–rare earth exploration target at Overland, with
geochemical and mineralogical characteristics interpreted to be consistent with a carbonatite mineral system.
• Pyrochlore, the dominant niobium ore mineral globally, has been identified through petrographic and Scanning
Electron Microscope (SEM) assessment of drill cuttings from OV167.
• OV167 was drilled above a large coherent magnetic anomaly, interpreted to potentially reflect Fe–Ti oxide
accumulation within basement rocks and presenting an immediate follow-up drilling target.
• The Company’s current interpretation is that OV167 may have intersected a sill or dyke-like expression of a
larger, untested carbonatite intrusive system nearby.
• Carbonatite mineral systems are globally important as major sources of rare earth elements and niobium (Nb).
• Clear forward work program: follow-up work is planned, including expanded geophysical modelling, detailed
petrographic and mineralogical assessment and targeted drilling to test the extent of the carbonatite
mineralising system, which typically extend for kilometre scales, and for the potential of shallow supergene
enriched portions of the carbonatite system to have developed.
• Engage with this announcement at the AR3 investor hub.
Cautionary Note: The Company cautions that the results reported are from a single drill hole. There is currently insufficient
data to define a Mineral Resource, and it is uncertain whether further exploration will result in the estimation of a Mineral
Resource. Early-stage results may not be representative of the overall target. However, the geological, geochemical and
mineralogical characteristics of OV167 support further systematic exploration of the R254 target.
Managing Director’s Comments:
“OV167 has delivered an exciting and unexpected technical result, the identification of a new niobium-rare earths
carbonatite mineral system at Overland.
“Importantly, this is not just a geochemical anomaly. The intersection includes elevated rare earths, niobium, titanium
and iron, together with petrographic and SEM evidence identifying pyrochlore, the principal niobium ore mineral
globally. These are encouraging early indicators of a fertile carbonatite-related mineral system.
“The result is particularly compelling because OV167 was drilled above a large coherent magnetic anomaly and ended
in anomalous basement-hosted mineralisation. Our current geological interpretation is that the hole may have
intersected a dyke or sill expression peripheral to a larger carbonatite intrusive centre, which remains untested and
represents the Company's next drilling target.
“While this is an early-stage result from a single drill hole and further work is required, the scale of the magnetic feature,
the mineral assemblage and the multi-element niobium–rare earth–titanium signature provide AR3 with a significant
new critical minerals exploration opportunity within the broader Overland Project, adding further exploration upside
alongside our uranium targets on the same tenure.
“Our immediate focus is to refine the exploration model through further mineralogical work, geophysical modelling and
targeted follow-up drilling to test the extent of this system and its potential for higher-grade or supergene-enriched
mineralisation.
“While the Overland carbonatite discovery represents an exciting new exploration opportunity for AR3, our priority
remains firmly on progressing the development of our flagship Koppamurra rare earths project. This discovery adds
further critical minerals upside to the portfolio, without changing our focus on advancing Koppamurra toward
commercialisation.”
Travis Beinke, Managing Director and CEO, Australian Rare Earths Limited
Figure 1 Drillhole Location Plan with Total Magnetic Intensity (TMI). South Australian regional total magnetic intensity images.
https://pid.sarig.sa.gov.au/dataset/mesac139
Figure 2 Drillhole Location with W-E section plan and Total Magnetic Intensity (TMI). South Australian regional total magnetic intensity
images. https://pid.sarig.sa.gov.au/dataset/mesac139
Exploration Results
Australian Rare Earths Limited (AR3 or the Company) has identified a significant new niobium–rare earth exploration target
at the R254 prospect within the Overland Project in South Australia.
The discovery was made during AR3's Sedan sedimentary-hosted uranium drilling program, highlighting the exploration
value of the Company's broad Overland landholding beyond its primary uranium targets.
Drill hole OV167 was completed to a depth of 105 metres. The hole intersected a broad interval of anomalous rare earth
and niobium mineralisation from 86 metres to end of hole, with elevated titanium, iron, barium and thorium supporting
interpretation of a carbonatite-related mineral system.
The identification of carbonatite-related geochemical and mineralogical characteristics in drill hole OV167 is considered
an encouraging early-stage exploration result. While further work is required to confirm the scale, geometry and economic
significance of the system, the presence of niobium and rare earth enrichment, together with diagnostic carbonatite-related
mineral phases, supports follow-up exploration at the R254 target.
Background: Carbonatite Mineral Systems
Carbonatites are a rare type of igneous rock characterised by a high proportion of carbonate minerals, typically calcite,
dolomite or iron-rich carbonate minerals. They commonly occur as intrusive bodies within alkaline igneous complexes and
may be expressed as plugs, dykes, sills, breccias, veins or associated alteration zones.
Globally, carbonatite systems are recognised as important hosts for a range of critical minerals, particularly rare earth
elements and niobium. They may also be enriched in phosphate, tantalum, uranium, thorium, copper, titanium, iron,
vanadium, barium, fluorine, zirconium and other elements, depending on the nature of the intrusive system and subsequent
alteration or weathering processes.
Carbonatite-related mineral systems are commonly associated with major crustal-scale structures and rift-related
tectonic settings. Their exploration footprint can be significantly larger than the intrusive body itself, with associated dykes,
sills, breccias and alteration halos providing important vectors toward the main mineralised system.
The identification of carbonatite-related geochemical and mineralogical characteristics in drill hole OV167 is therefore
considered an encouraging early-stage exploration result. While further work is required to confirm the scale, geometry and
economic significance of the system, the presence of niobium and rare earth enrichment, together with diagnostic
carbonatite-related mineral phases, supports follow-up exploration at the R254 target.
Carbonatite deposits represent a significant source of global rare earth and niobium production, including major rare earth
deposits such as Bayan Obo in Inner Mongolia and Mt Weld in Western Australia, as well as the world’s principal operating
niobium mines.
Methodology
The drillhole was geologically logged on-site via 1m sample intervals being returned to surface and by a gamma probe run
downhole through the drill string (rods) at the completion of the hole to provide a survey of the background radiometric
response of the geological units intersected – see cross section Figure 3.
Selected samples were collected for assay, and the results were uploaded to the AR3 database. Key element
concentrations determined by assay (total rare earths, niobium and barium) are displayed downhole – see cross section
Figure 3. Additional assayed elemental concentrations of interest are shown in Table 1.
The overall drilling program comprised 22 holes for 1,280m (Figure 1), and aimed to test two large sedimentary-hosted
uranium target zones defined by historic drilling. The drilling, sampling and assay results continue to indicate anomalous
uranium accumulations in the sedimentary sequence, however no significant intersections were identified.
Figure 3, W-E Section displaying downhole; lithology, gamma response (cps), assays for TREO, Niobium and Barium
Table 1, individual 1m intervals from the zone of interest in drillhole OV167, with assay results for Total Rare Earth Oxide (TREO),
(including key rare earth assemblage details) and Niobium, Titanium, Iron, Thorium and Barium.
Hole ID
From
(m)
To
(m)
Sample
ID
TREO
(ppm)
NdPr
%of
TREO
DyTb
%of
TREO
Nb2O5
(ppm)
TiO2
(%)
Fe2O3
(%)
Th
(ppm)
Ba
(ppm)
Geology
OV167 86 87 743334 2,740 17% 4.6% 2,289 4.65 4.8 675 288 Saprolite
OV167 87 88 743335 10,322 19% 2.7% 5,264 6.29 5.7 2,400 1,300 Saprolite
OV167 88 89 743336 6,098 19% 2.0% 2,689 4.35 12.0 632 6,420 Saprolite
OV167 89 90 743337 5,373 19% 2.4% 2,346 3.92 16.6 1,090 5,880 Saprolite, ~5% sulphides
OV167 90 91 743338 5,739 22% 1.7% 2,861 3.07 13.5 717 6,100 Saprolite, fault (?)
OV167 91 92 743339 3,036 22% 1.5% 2,003 2.94 10.5 352 6,240 Saprolite, fault (?)
OV167 92 93 743340 5,934 19% 0.9% 1,545 2.57 11.9 529 5,540 Saprolite, fault (?)
OV167 93 94 743341 12,026 17% 0.9% 472 2.10 11.3 1,930 9,540 Basement, ~5% sulphides
OV167 94 95 743342 10,726 18% 0.7% 494 2.69 19.6 1,070 14,300 Basement, ~5% sulphides
OV167 95 96 743343 12,127 17% 0.6% 522 2.67 14.7 1,090 10,400 Basement, ~5% sulphides
OV167 96 97 743344 3,423 19% 0.9% 479 2.55 11.9 176 7,160 Basement, ~5% sulphides
OV167 97 98 743345 6,327 21% 1.3% 794 4.09 19.4 321 10,200 Basement, ~5% sulphides
OV167 98 99 743346 5,285 23% 1.6% 644 4.17 23.9 346 10,200 Basement, ~5% sulphides
OV167 99 100 743347 5,748 23% 2.1% 579 2.84 18.7 411 7,420 Basement, ~5% sulphides
OV167 100 101 743348 4,279 22% 2.4% 694 4.19 17.6 195 11,400 Basement, ~5% sulphides
OV167 101 102 743349 3,201 22% 2.5% 815 5.74 17.9 185 8,040 Basement
OV167 102 103 743350 4,257 23% 1.5% 672 4.09 15.7 138 9,180 Basement
OV167 103 104 743351 4,771 24% 1.5% 858 3.75 18.9 184 9,380 Basement
OV167 104 105 743352 4,566 23% 1.2% 794 3.7 21.2 149 10,800 Basement
Significant intersections include:
• 7m @ 0.56% TREO with 0.27% Nb2O5, and 4.0% TiO2, from 86m
• Including 1m @ 1.0% TREO with 0.53% Nb2O5, and 6.3% TiO2, from 87m
• 3m @ 1.16% TREO, from 93m
• 9m @ 0.46% TREO, from 96m with 3.9% TiO2
• Including 3m @ 0.57% TREO, from 97m
The mineralised interval is associated with a large coherent magnetic anomaly, interpreted as potentially reflecting Fe–Ti
oxide accumulation within basement rocks. AR3 considers this an important exploration vector, and the current working
model suggests that OV167 may have intersected a sill or dyke-like feature associated with a larger, untested carbonatite
intrusive body. This represents an immediate target for follow up drilling – see Figure 1.
This geological setting is supported by the exploration models outlined in Simandl & Paradis (2018)1
and described in Figure
4. They note that carbonatites commonly occur as isolated pipes, sills, dykes, or plugs, or as part of alkaline-carbonatite
complexes, incorporating cone sheets, ring dykes, radial dykes, and especially fenitisation-type halos (alkali
metasomatism). This model significantly increases the target footprint as fenitisation aureoles can substantially expand
the detectable size of carbonatite systems and often serve as a key vector to larger intrusions even where the main
carbonatite body has not been directly intersected.
Elevated niobium (Nb), iron (Fe), rare earth elements (REE) and thorium (Th) are consistent with the geochemical signature
expected within the distal carbonatitic-fluid domain shown on the right-hand side of the hypothetical carbonatite
mineralising system shown in Figure 4. This style of mineralisation is compatible with recognised carbonatite systems
where late carbohydrothermal fluids transport and precipitate Nb and REE along structural conduits beyond the principal
intrusive centre.
1
George J. Simandl & Suzanne Paradis (2018) Carbonatites: related ore deposits, resources, footprint, and exploration methods, Applied Earth Science,
127:4, 123-152, DOI: 10.1080/25726838.2018.1516935
Australian comparisons for this style of mineralisation include:
• The Lynas Ltd Mt Weld Carbonatite (Western Australia) is one of the world's highest-grade Rare Earth Element (REE)
deposits. Discovered in 1966 via aeromagnetic surveys, it features a 3-kilometer-wide, sub-vertical volcanic pipe
containing high concentrations of rare earths, niobium, and phosphate.
• West Arunta Region (e.g., Luni Niobium Project – WA1 Resources): Carbonatite-hosted niobium and REE
mineralisation linked to prominent magnetic anomalies, highlighting the scale potential of these systems in
Australia.
Figure 4; Vertical section of a hypothetical carbonatite mineralising system displaying the relationship between metallic and industrial
mineral deposits relative to lithological units and geological contacts. The ‘distal’ carbo-hydrothermal fluid-related mineralisation or
hydrothermally remobilised mineralisation (away from alkaline-carbonatite complex) and residual deposits within weathered crust
above the carbonatite complex are also highlighted. Bi – biotite, Px- pyroxene. Modified from Laznicka.
Initial petrographic and mineralogical assessment, including thin-section examination, SEM and mineral chemistry, has
identified key carbonatite related mineral phases. Pyrochlore is the principal niobium-bearing ore mineral in major niobium
deposits globally.
Further detailed petrographic and mineralogical assessments will be used to refine the exploration model and evaluate the
potential proximity to a larger nearby alkaline-carbonatite system.
Next Steps
• Detailed mineralogical/petrographic assessment through thin section and SEM.
• Expanded geophysical modelling (gravity gradiometry, and magnetics) and further evaluation of the fenitisation
halo across the project area.
• Follow-up diamond and RC drilling to delineate the sill/dyke geometry and test for the potential of a larger nearby
carbonatite system.
The announcement has been authorised for release by the Board of Australian Rare Earths Limited.
For further information please contact:
Australian Rare Earths Limited Media Enquiries
Travis Beinke Jessica Fertig
Managing Director and CEO Tau Media
T: 1 300 646 100 E: info@taumedia.com.au
Engage and Contribute at the AR3 investor hub: https://investorhub.ar3.com.au
Competent Person’s Statement
The information in this report that relates to Exploration results is based on information compiled by Australian Rare Earths Limited and reviewed
by Mr Rick Pobjoy who is the Chief Technical Officer of the Company and a member of the Australian Institute of Mining and Metallurgy (AusIMM).
Mr Pobjoy has sufficient experience that is relevant to the style of mineralisation, the type of deposit under consideration and to the activities
undertakentoqualifyas aCompetentpersonas definedinthe2012editionofthe“AustralasianCodeforReportingofExplorationResults, Mineral
Resources and Ore Reserves”. Mr Pobjoy consents to the inclusion in this report of the matters based on this information in the form and context
in which it appears.
Forward-Looking Statements
This announcement contains forward-looking statements. Such statements are based on the Company’s current expectations and are subject to
risks and uncertainties. Actual results may differ materially from those expressed or implied. Reference to the Simandl & Paradis (2018) paper is
for contextual exploration modelling purposes only.
About Australian Rare Earths Limited
Australian Rare Earths (AR3) is a diversified critical minerals company, strategically positioned to meet the growing global demand for uranium and
rare earth elements:
• AR3's Koppamurra Rare Earths Project in South Australia and Victoria is a significant deposit of light and heavy rare earths, which has secured
important Australian government support through a $5 million grant to accelerate development. With support from global advanced industrial
materials manufacturer, Neo Performance Materials, AR3 is progressing towards commercialisation with a Pre-Feasibility Study, Maiden Ore
Reserves and a pilot scale facility, solidifying its role in diversifying global rare earth supply chains for the clean energy transition.
• AR3’s large ~8,000 km² Overland Uranium Project in South Australia shows strong uranium discovery potential, with initial drilling identifying
opportunities for substantial near-surface and deeper deposits.
With strategic projects and strong government support, AR3 is poised for significant growth in the critical minerals market.
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
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 (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 to obtain samples from
the April/May 2026 drilling program centered on the town of
Sedan.
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. 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 pXRF Analyser (Model Vanta M
Series S/N 842924) was used to assess the geochemistry of the
Air Core samples in the field. The pXRF analysis provided
screening analysis to characterize the sample lithology and full
suite of elements.
The pXRF sampling was analysed through the calico bag with a
beam count time of 20-30 sec beam 1 and 10 sec beam 2. One
pXRF analysis per sample was performed.
Samples are laid on a workbench and flattened to create a
stable surface for the pXRF. The pXRF is placed on the sample
with the beam down for the analysis.
All readings were taken at ambient temperatures between 10
and 45 degrees Celsius. The Olympus Vanta is rated for
continuous operation within these temperatures.
Samples range from dry to wet, this is dependent on which
formation is being intercepted and whether drilling water has
been injected.
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.
A Uranium standard Oreas 121 (215 ppm U, sourced from
Mantra Resources Nyota Prospect, Tanzania, which is a
Tabular Sandstone hosted deposit) was used to verify the
accuracy of the pXRF before and after each analysis session.
The OREAS 121 standard was prepared using an industry
standard pXRF sample cup and analysed for 20-30 sec on
beam 1 and 10 Sec on beam 2.
A silica blank is used to monitor the accumulation of
contamination on the lens of the pXRF. Analysis of the blank
is undertaken before and after each analysis session.
Review of pXRF standard and blank data is checked to
ensure the pXRF is operating correctly before and after
each session.
Samples were selected for assay at the end of the hole
based on geology, pXRF, and natural downhole gamma
response.
Field duplicates were taken at a rate of ~1:40 and inserted
blindly into the sample batches.
Field Standards were taken at a rate of ~1:40 and inserted
blindly into the samples batches.
Samples were submi ed to Bureau Veritas in Adelaide,
where wet and dry sample weights were recorded before
oven drying at 105 degrees Celsius for a minimum of 24
hours. Samples were then secondary crushed to 3 mm and
pulverised to 90% passing 75 µm, with excess residue
retained for storage and selected material submitted for
analysis using the XRF-ICP-MS method.
The samples were submitted for analysis using Mixed Acid
Digest – Lithium Borate Fusion ICP-MS method (BV Code
SC302) with detection limits for each element shown in ppm
Ag (0.2 ppm), Al (50.0 ppm), As (1.0 ppm), Au (0.01 ppm),
Ba (2.0 ppm), Be (0.5 ppm), Bi (0.1 ppm), Ca (100.0 ppm),
Cd (0.5 ppm), Ce (0.1 ppm), Co (1.0 ppm), Cr (20.0 ppm), Cs
(0.1 ppm), Cu (1.0 ppm), Dy (0.05 ppm), Er (0.05 ppm), Eu
(0.05 ppm), Fe (100.0 ppm), Ga (0.2 ppm), Gd (0.2 ppm), Hf
(1.0 ppm), Ho (0.02 ppm), In (0.05 ppm), K (100.0 ppm), La
(0.1 ppm), Li (10.0 ppm), Lu (0.02 ppm), Mg (50.0 ppm), Mn
(50.0 ppm), Mo (0.5 ppm), Na (100.0 ppm), Nb (0.5 ppm),
Nd (0.05 ppm), Ni (2.0 ppm), P (50.0 ppm), Pb (1.0 ppm), Pr
(0.05 ppm), Rb (0.2 ppm), Re (0.1 ppm), S (50.0 ppm), Sb
(0.1 ppm), Sc (1.0 ppm), Se (5.0 ppm), Si (50.0 ppm), Sm
(0.05 ppm), Sn (0.1 ppm), Sr (0.5 ppm), Ta (0.1 ppm), Tb
(0.02 ppm), Te (0.2 ppm), Th (0.1 ppm), Ti (50.0 ppm), Tl
(0.1 ppm), Tm (0.05 ppm), U (0.1 ppm), V (20.0 ppm), W
(0.5 ppm), Y (1.0 ppm), Yb (0.05 ppm), Zn (2.0 ppm), Zr
(10.0 ppm)
Select samples, often at the bottom of the holes thought to
be weathered basement/saprolite material were also
analyzed for gold using Lead collection Fire Assay AAS (BV
Code FA001) where a detection limit for Au (0.01 ppm)
Laboratory repeat analyses were completed at an
approximate frequency of 1 in 16 samples.
Commercially sourced cer fied reference materials were
inserted by the laboratory into the sample sequence at an
approximate frequency of 1 in 5 samples.
Laboratory blanks were inserted into the sample sequence
at an approximate frequency of 1 in 50 samples.
After the hole was drilled to completion a Reflex EZ Gamma
logging tool (serial number GAM-105) rented from Imdex,
and operated by the drilling crew was run down the hole,
inside the rods/innertube to log the natural gamma response
of the sediments. The gamma tool was last calibrated by
Imdex on February 19th, 2026, as noted in the provided
Certificate of Conformance. Confidence check jig serial
number 030.
The survey was run in and out of the hole at a speed of no
more than 10m/min and the downhole speed was reviewed
after the survey.
The up (out) survey was then used to plot sections, after
reviewing both in and out.
In previous drilling at Overland, the Reflex EZ-Gamma logging
tool was checked with an EZ-Gamma Confidence Checker by
AR3 staff before each downhole gamma survey to verify
instrument performance. Based on the demonstrated
reliability and consistency of the EZ-Gamma tool during
previous programs, it was determined that routine confidence
checks were not necessary for this shorter drilling campaign.
Instead, the repeatability of the gamma data was assessed by
comparing the downhole (in-run) and uphole (out-run)
surveys.
After completion of each gamma survey, the in-run and out-
run datasets were reviewed and compared to confirm data
repeatability and identify any significant discrepancies that
could indicate instrument drift or logging issues. Any
inconsistencies would have triggered further investigation
and, if required, a repeat survey.
After the gamma survey is completed, the data is uploaded to
the Imdex hub IQ portal (https://iq.imdexhub.com) from the
rig via satellite internet and available for review.
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 Wallis “Mantis 100” air core drill
rig 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
27- 105m depth.
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.
Drilling commonly advanced from unconsolidated Murray
Basin sediments into saprolitic bedrock, with sample quality
varying in basement zones where interpreted faults were
intersected. These zones were logged at one-metre intervals
and assigned a sample quality a ribute.
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 disposed of
in a sump below the cyclone/rotary splitter.
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 has been iden fied between sample
recovery and grade at this early stage of exploration.
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.
The density drilling is not sufficient to support consideration of
resource estimation, or mining and no geotechnical logging was
completed.
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 to ensure that the
sampling is representative of the in-
situmaterial 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.
1 m aircore sample interval were homogenised within the
cyclone and the rotary splitter was set to an approximate 20%
split producing around 1.5 kg sample for each metre interval.
The 1.5 kg sample was collected in a pre- numbered calico
bags and the remaining 80% (5 kg to 8 kg) was disposed of
in a sump below the cyclone/rotar
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