Metallurgical Optimisation Update
In brief · summary, not quotable
Cobra Resources PLC has announced significant metallurgical optimisation results from its Boland in situ recovery project, demonstrating the successful removal of 100% of low-value cerium from the pregnant liquor solution. This process, conducted at ambient temperature and pressure, substantially increases the value of the product by approximately 50%, with the upgraded Mixed Rare Earth Carbonate expected to contain around 38% magnet rare earths and 47% heavy rare earths. High-quality cerium carbonate will be available as a separate by-product, and the company plans to incorporate these findings into its draft Process Flowsheet, with further optimisation studies expected by the end of December 2025.
Full announcement
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Cobra (LSE: COBR), a South Australian mineral exploration and development company, is pleased to announce further highly favourable results from flowsheet optimisation studies aimed at reducing cost and maximising the value of strategic rare earth elements ("REEs") from its Boland in situ recovery ("ISR") project in South Australia.
In 2023 Cobra discovered ionic REEs in permeable sands (confined between impermeable aquicludes) at Boland. In-field tracer studies have since shown that this mineralisation is potentially recoverable in a pregnant liquor solution ("PLS") using low-cost/low-impact ISR techniques.
Cobra is now able to announce that additional test work by the Australian Nuclear and Scientific Technology Organisation ("ANSTO") has shown that 100% of the (low value and relatively abundant) cerium content can be removed from the PLS at ambient temperature and pressure with minimal loss of the high-value magnet and heavy REEs (principally dysprosium and terbium).
The Company intends now to incorporate these results into its draft Process Flowsheet with the intention of producing a high-value Mixed Rare Earth Carbonate ("MREC"), exceptionally enriched in high-value magnet and heavy REEs. The removal of cerium would ultimately simplify REE separation for future customers, increasing product value and marketability.
High-quality cerium carbonate is expected to be available as a separate by-product.
Follow this link to watch a short video of MD Rupert Verco explaining the results released in this announcement: https://investors.cobraplc.com/link/PKa9Be.
Highlights:
- ANSTO test work has shown that up to 100% of the (low value) cerium can be removed from Boland PLS in aqueous solution at ambient temperatures and pressure, thereby upgrading the potential MREC per kilogram value by approximately 50%
- The resultant upgraded potential MREC product is expected to contain approximately 38% Magnet Rare Earths and 47% Heavy Rare Earths
- Cerium carbonate is expected to be sold as a separate by-product
Further work:
- The draft Boland Process Flowsheet is being amended to provide for cerium precipitation and removal, and this amended Flowsheet will be trialled using the 77 litres of PLS which is available from an earlier leach-trial of a 55kg composite sample of Boland mineralisation
- Flowsheet optimisation studies will continue, and a next-generation version of the Boland Process Flowsheet is expected to be available by the end of December 2025
- The results of further test work will be announced as they become available and samples of the resultant MREC will be made available to potential off-take partners
Rupert Verco, Managing Director of Cobra, commented:
"This is a significant outcome and makes our future product extremely valuable and market leading in heavy REE composition. Cobra is driving innovation in REE recovery enabled by low-costs and unique mineralisation characteristics.
As we advance the Boland Project we seek to identify and address both risk and opportunity. The work we have completed during 2025 has both addressed technical risk and defined considerable opportunities. Cobra is well positioned to build on this work in 2026 with the resource definition aiming to support financial modelling that will demonstrate the value of the work programmes completed.
Due to its environmental credentials, the Boland Project is emerging as the most ethical source of dysprosium and terbium to support electrification."
What makes this test work so important?
- MRECs comprise variable quantities of 15 lanthanides (plus scandium and yttrium), where each rare earth varies in commercial value and natural abundance. Cerium and lanthanum are the most abundant and least valuable
- By reducing the less valuable REEs, the ratios of valuable REEs in the MREC are maximised and the processes in downstream separation are simplified
- This test work has successfully demonstrated that the proportion of valuable REEs can be materially increased:
o Dy+Tb from 4.1% to 5.7% of TREO
o Nd+Pr from 21.5% to 32.6% of TREO
o HREO from 30.5% to ~48% of TREO
- This process step is expected to greatly increase product demand and marketability to future customers
Table 1: TREO distribution in PLS before and after at varying pH
| pH3 | pH3 | pH4.5 | pH5 | |||||
|---|---|---|---|---|---|---|---|---|
| REO | PLS (mg/l) | % of TREO in PLS | % of TREO at CeO4-600mV | % of TREO at CeO4-150% | % TREO at CeO4-300% | % of TREO at CeO4-600mV | % of TREO at CeO4-150% | % TREO at CeO4-300% |
| La | 26 | 12% | 13.5% | 17.9% | 19.2% | 14.3% | 19.0% | 20.1% |
| Ce | 77 | 36% | 28.9% | 8.2% | 0.3% | 26.3% | 3.9% | 0.0% |
| Pr | 9 | 4% | 4.9% | 5.9% | 6.7% | 4.9% | 6.3% | 6.5% |
| Nd | 37 | 17% | 18.7% | 24.5% | 25.9% | 19.6% | 25.0% | 25.8% |
| Sm | 8 | 4% | 4.1% | 4.9% | 5.5% | 4.0% | 5.1% | 5.2% |
| Eu | 2 | 1% | 0.8% | 1.0% | 1.1% | 0.8% | 1.0% | 1.1% |
| Gd | 8 | 4% | 4.2% | 5.2% | 5.8% | 4.3% | 5.6% | 5.8% |
| Tb | 1 | 1% | 0.6% | 0.7% | 0.8% | 0.6% | 0.8% | 0.8% |
| Dy | 7 | 3% | 3.5% | 4.3% | 4.9% | 3.5% | 4.5% | 4.7% |
| Ho | 1 | 1% | 0.7% | 0.9% | 1.0% | 0.7% | 0.9% | 0.9% |
| Er | 3 | 2% | 1.8% | 2.2% | 2.5% | 1.8% | 2.3% | 2.4% |
| Tm | 0 | 0% | 0.2% | 0.3% | 0.3% | 0.2% | 0.3% | 0.3% |
| Yb | 2 | 1% | 1.2% | 1.4% | 1.6% | 1.2% | 1.5% | 1.5% |
| Lu | 0 | 0% | 0.2% | 0.2% | 0.2% | 0.2% | 0.2% | 0.2% |
| Y | 33 | 15% | 16.9% | 22.4% | 24.2% | 17.7% | 23.6% | 24.7% |
| HREO | 66.12 | 30.55% | 34.0% | 43.4% | 47.9% | 34.9% | 45.8% | 47.6% |
| MREO | 54.47 | 25.17% | 27.7% | 35.5% | 38.2% | 28.6% | 36.6% | 37.8% |
| Nd + Pr | 46.53 | 21.50% | 23.6% | 30.5% | 32.6% | 24.5% | 31.3% | 32.3% |
| Dy + Tb | 7.94 | 3.67% | 4.1% | 5.0% | 5.7% | 4.1% | 5.3% | 5.5% |
Table 2: Percentage of precipitation achieved at varying acidities and reagent addition
| pH | 4.5 | 4.5 | 4.5 | 5 | 5 | 5 |
| REE | CeO4-600mV | CeO4-150% | CeO4-300% | CeO4-600mV | CeO4-150% | CeO4-300% |
| La | 0.6 | <1 | 3 | 3 | 6 | 6 |
| Ce | 28 | 84 | 99 | 39 | 94 | 100 |
| Pr | <1 | 4 | 5 | 6 | 12 | 14 |
| Nd | 2 | 0.2 | 7 | 6 | 12 | 14 |
| Sm | <1 | 4 | 6 | 8 | 15 | 17 |
| Eu | <1 | 4 | 6 | 7 | 13 | 16 |
| Gd | 0.6 | 4 | 5 | 6 | 10 | 13 |
| Tb | 0.7 | 4 | 5 | 7 | 12 | 14 |
| Dy | 1.0 | 4 | 4 | 8 | 13 | 15 |
| Ho | 2 | 4 | 5 | 9 | 13 | 14 |
| Er | 2 | 5 | 6 | 9 | 14 | 15 |
| Tm | 3 | 6 | 6 | 10 | 16 | 18 |
| Yb | 4 | 8 | 7 | 12 | 19 | 21 |
| Lu | 4 | 6 | 7 | 12 | 19 | 20 |
| Y | 0.2 | <1 | 1.4 | 4 | 6 | 7 |
Table 3: Estimated basket value based on quote Rare Earth Oxide Prices on the Shanghai Metals Market. Optimised basket distribution is based on pH 4.5 % TREO at CeO4-300%
| REO | Shanghi Metal Market ($USD) 1 | Unoptimised PLS value per kg TREO ($USD) | Optimised PLS value per kg TREO ($USD) |
|---|---|---|---|
| La2O3 | $0.61 | $0.07 | $0.12 |
| CeO2 | $1.59 | $0.57 | $0.01 |
| Pr6O11 | $80.63 | $3.48 | $5.37 |
| Nd2O3 | $80.28 | $13.80 | $20.79 |
| Sm2O3 | $2.33 | $0.08 | $0.13 |
| Eu2O3 | $60.03 | $0.43 | $0.66 |
| Gd2O3 | $22.47 | $0.85 | $1.31 |
| Tb2O3 | $910.45 | $4.96 | $7.64 |
| Dy2O3 | $205.02 | $6.40 | $9.95 |
| Ho2O3 | $73.03 | $0.46 | $0.71 |
| Er2O3 | $226.63 | $3.64 | $5.57 |
| Tm2O3 | $160.09 | $0.31 | $0.48 |
| Yb2O3 | $13.43 | $0.15 | $0.22 |
| Lu2O3 | $610.34 | $0.92 | $1.39 |
| Y2O3 | $6.37 | $0.96 | $1.54 |
| Basket Value | $37.08 | $55.88 | |
| Assumed Payability | 70% | $25.96 | $39.12 |
1 1 December 2025, inclusive 13% VAT
2 Payability rate based on offtake discussions and other published market pricing assumptions
The economic value of this test work cannot be reasonably assessed until an optimised MREC has been produced and offtake testing has progressed.
The significant increase in cerium removal along with the reduced reagent usage support significant advancement in the economic potential. While co-precipitation of valuable REEs appears problematic; the mechanisms for co-precipitation are well understood and further test work that is designed to demonstrate capture and return these REE is being developed. This should enable valuable REEs to be easily returned to solution and captured within the flowsheet. Tests are being devised to demonstrate this. The Company is now evaluating the engineering parameters of the draft flowsheet.
About the Boland Project
Further information relating to Boland and these results are presented in the appendices.
- Exploration update: Successful first pass suppression of cerium to maximise valuable dysprosium and terbium
- Exploration update: "Exceptional Results - Infield Permeability Study", dated 17 November 2025
- Exploration update: "Metallurgical Optimisation Upside", dated 20 October 2025
- Exploration update: "Exceptional Metallurgical Results from ISR Column", dated 14 October 2025
- Exploration update: "Met Study Supports Even Lower-Cost Recoveries", dated 11 September 2025
- Exploration update: "Low-Cost Recoveries from Optimised Testing", dated 11 August 2025
- Exploration update: "Rare Earth ISR System beyond Boland", dated 4 August 2025
- Exploration update: "Favourable Boland Metallurgical Results", dated 21 July 2025
- Exploration update: "Boland Project Update", dated 26 June 2025
- Wudinna Project Update: "Boland Aircore Drill Results", dated 25 February 2025
- Wudinna Project Update: "2nd Bench Scale ISR Study & £1.7M Placing", dated 26 November 2024
- Wudinna Project Update: "ISR Bench Scale Study Completion", dated 4 November 2024
of heavy rare earths", dated 28 August 2024
Regional map showing Cobra's tenements in South Australia
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Appendix 1: Background information - the Boland Project and ISR
Figure A1: Comparison between the Chinese and the proposed Boland process for ISR mining of REEs
Appendix 2: JORC Code, 2012 Edition - Table 3
| Criteria | JORC Code explanation | Commentary |
| Sampling techniques | · Nature and quality of sampling (eg cut channels, random chips, or specific specialised industry standard measurement tools appropriate to the minerals under investigation, such as down hole gamma sondes, or handheld XRF instruments, etc). These examples should not be taken as limiting the broad meaning of sampling. · Include reference to measures taken to ensure sample representivity and the appropriate calibration of any measurement tools or systems used. · Aspects of the determination of mineralisation that are Material to the Public Report. · In cases where 'industry standard' work has been done this would be relatively simple (eg 'reverse circulation drilling was used to obtain 1 m samples from which 3 kg was pulverised to produce a 30 g charge for fire assay'). In other cases more explanation may be required, such as where there is coarse gold that has inherent sampling problems. Unusual commodities or mineralisation types (eg submarine nodules) may warrant disclosure of detailed information. | Pre 2023 · Historic Rotary Mud drilling targeting paleochannel hosted uranium was completed. Some residue samples were retained in the Tonsley Core Library, downhole geophysical logging was the primary data collected for these holes. · Select historic sample residues over Boland were analysed as reported in RNS 1834M (26 April 2024) 2023 Aircore · A combination of 2m and 3m samples were collected in green bags via a rig mounted cyclone. A PVC spear was used to collect a 2-4kg sub sample from each green bag. Sampling commenced from the collar point with samples submitted for analysis from the top of saprolite. · Samples were submitted to Bureau Veritas Laboratories, Adelaide and pulverized to produce a 4-acid digest sample. 2024-2025 SONIC · Drill results are outlined in RNS 0297I (25 March 2024) · 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 were submitted to Bureau Veritas Laboratories, Adelaide and pulverized to produce a 4 acid digest sample. Aircore · 1m sample intervals of 2-4 kg were taken via PVC spear from green bags at the rig. Select samples were submitted to the lab for analysis. From 0-6 m in each hole samples were composited to 3m. · Samples were submitted to Bureau Veritas Laboratories, Adelaide and pulverized to produce a 4 acid digest sample. |
| Drilling techniques | · Drill type (eg core, reverse circulation, open-hole hammer, rotary air blast, auger, Bangka, sonic, etc) and details (eg core diameter, triple or standard tube, depth of diamond tails, face-sampling bit or other type, whether core is oriented and if so, by what method, etc). | Pre 2023 · Drill methods include Rotary Mud and AC 2023 · Drilling completed by McLeod Drilling Pty Ltd using 75.7mm NQ air core drilling techniques from an ALMET aircore rig mounted on a Toyota Landcruiser 6x6 and a 200psi, 400cfm Sullair compressor. 2024-2025 · 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 · Aircore Drilling completed by McLeod Drilling Pty Ltd using 75.7mm NQ air core drilling techniques from an ALMET aircore rig mounted on a Toyota Landcruiser 6x6 and a 200psi, 400cfm Sullair compressor. |
| Sub-sampling techniques and sample preparation | · If core, whether cut or sawn and whether quarter, half or all core taken. · If non-core, whether riffled, tube sampled, rotary split, etc and whether sampled wet or dry. · For all sample types, the nature, quality and appropriateness of the sample preparation technique. · Quality control procedures adopted for all sub-sampling stages to maximise representivity of samples. · Measures taken to ensure that the sampling is representative of the in situ material collected, including for instance results for field duplicate/second-half sampling. · Whether sample sizes are appropriate to the grain size of the material being sampled. | Pre 2023 · Historic Residue samples were generally 2m composites and were stored at the South Australian Drill Core Reference Library at Tonsley, a subsample of approximately 20g was removed for lab submission. · Select samples of geological interest were selected for lab submission · No QAQC samples were included in the submission of these samples. Sample results were intended to indicate mineralisation potential but would not be suitable for resource estimation Post 2023 · A PVC spear was used to collect 2-4kg of sub-sample from each AC sample length controlled the sample volume submitted to the lab. · Additional sub-sampling was performed through the preparation and processing of samples according to the Bureau Veritas internal protocols. · Field duplicate AC samples were collected from the green bags using a PVC spear scoop at a 1 in 25 sample frequency. · Sample sizes are considered appropriate for the material being sampled. · Assessment of duplicate results indicated this sub - sample method provided appropriate repeatability for rare earths. 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 2024. · For 2025 drilling, quarter core was submitted to the lab for geochemical testing. · In holes where only column leach test samples have been submitted, full core samples have been submitted. In holes where geochemical samples were submitted three quarter core sanmples were submitted for column leach testing.. |
| Quality of assay data and laboratory tests | · The nature, quality and appropriateness of the assaying and laboratory procedures used and whether the technique is considered partial or total. · For geophysical tools, spectrometers, handheld XRF instruments, etc, the parameters used in determining the analysis including instrument make and model, reading times, calibrations factors applied and their derivation, etc. · Nature of quality control procedures adopted (eg standards, blanks, duplicates, external laboratory checks) and whether acceptable levels of accuracy (ie lack of bias) and precision have been established. | · Samples were submitted to Bureau Veritas, Adelaide for preparation and analysis. Multi-element geochemistry were digested by four acid ICP-MS/ ICP-OES and analysed for Ag, Ce, Cu, Dy, Er, Eu, Gd, Ho, La, Lu, Mg, Na, Nd, P, Pr, Sc, Sm, Tb, Th, Tm, U, Y and Yb. · Field 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 pass the companies implemented QAQC database reports · Internal lab blanks, standards and repeats for rare earths indicated acceptable assay accuracy. Sample Characterisation Test Work performed by the Australian Nuclear Science and Technology Organisation (ANSTO) · Full core samples were submitted to Australian Nuclear Science and Technology Organisation (ANSTO), Sydney for preparation and analysis. The core was split in half along the vertical axis, and one half further split into 10 even fractions along the length of the half-core. Additional sub-sampling, homogenisation and drying steps were performed to generate ~260 g (dry equivalent) samples for head assay according to the laboratory internal protocols. · Multi element geochemistry of solid samples were analysed at ANSTO (Sydney) by XRF for the major gangue elements Al, Ca, Fe, K, Mg, Mn, Na, Ni, P, Si, S, and Zn. · Multi element geochemistry of solid samples were additionally analysed at ALS Geochemistry Laboratory (Brisbane) on behalf of ANSTO by lithium tetraborate digest ICP-MS and analysed for Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Pr, Sm, Tb, Th, Tm, U, Y and Yb. · Reported assays are to acceptable levels of accuracy and precision. · Internal laboratory blanks, standards and repeats for rare earths indicated acceptable assay accuracy. · Samples retained for metallurgical analysis were immediately vacuum packed, nitrogen purged and refrigerated. · These samples were refrigerated throughout transport. Metallurgical Leach Test Work performed by the Australian Nuclear Science and Technology Organisation (ANSTO) · ANSTO laboratories prepared ~80g samples for diagnostic leaches, a 443g sample for a slurry leach and a 660g sample for a column leach. Sub-samples were prepared from full cores according to the laboratory internal protocols. Diagnostic and slurry leaching were carried out in baffled leach vessels equipped with an overhead stirrer and applying a 0.5 M (NH4)2SO4 lixiviant solution, adjusted to the select pH using H2SO4. · 0.5 M H2SO4 was utilised to maintain the test pH for the duration of the test, if necessary. The acid addition was measured. · Thief liquor samples were taken periodically. · At the completion of each test, the final pH was measured, the slurry was vacuum filtered to separate the primary filtrate. · The thief samples and primary filtrate were analysed as follows: o ICP-MS for Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Mn, Nd, Pb, Pr, Sc, Sm, Tb, Th, Tm, U, Y, Yb. o ICP-OES for Al, Ca, Fe, K, Mg, Mn, Na, Si. · The water wash was stored but not analysed. · Column leaching was carried out in horizontal and vertical leaching columsn. The column was pressurised with nitrogen to 2.5 bar and maintained at ambient temperature · A 0.3 M (NH4)2SO4 lixiviant solution, adjusted to the select pH using H2SO4 was fed to the column at a controlled flowrate. · PLS collected from the end of the column was weighed, the EH and pH measured and the free acid concentration determined by titration. Liquor samples were taken from the collected PLS and analysed as follows: o ICP-MS for Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Mn, Nd, Pb, Pr, Sc, Sm, Tb, Th, Tm, U, Y, Yb. o ICP-OES for Al, Ca, Fe, K, Mg, Mn, Na, Si. · The column leach test has been completed. Assays of the column have adjusted head grades of the initial bench scale study. Recoveries have been adjusted accordingly. · A subsample of the pregnant liquor produced from the column leach has been used for flowsheet optimization tests · Cerium removal tests have been performed using selected reagents aimed at precipitating Cerium. · Reported results are presented by percentage increase in dose (stoichiometric to Ce after adjustment to 600 mV) |
| Verification of sampling and assaying | · The verification of significant intersections by either independent or alternative company personnel. · The use of twinned holes. · Documentation of primary data, data entry procedures, data verification, data storage (physical and electronic) protocols. · Discuss any adjustment to assay data. | · Sampling data was recorded in field books, checked upon digitising and transferred to database. · Geological logging was undertaken digitally via the MX Deposit logging interface and synchronised to the database at least daily during the drill programme. · Compositing of assays was undertaken and reviewed by Cobra Resources staff. · Original copies of laboratory assay data are retained digitally on the Cobra Resources server for future reference. · Samples have been spatially verified through the use of Datamine and Leapfrog geological software for pre 2021 and post 2021 samples and assays. · Twinned drillholes from pre 2021 and post 2021 drill programs showed acceptable spatial and grade repeatability. · Physical copies of field sampling books are retained by Cobra Resources for future reference. · Significant intersections have been prepared by Mr Robert Blythman and reviewed by Mr Rupert Verco |
| Location of data points | · Accuracy and quality of surveys used to locate drill holes (collar and down-hole surveys), trenches, mine workings and other locations used in Mineral Resource estimation. · Specification of the grid system used. · Quality and adequacy of topographic control. | 2021-2023 · 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 2024 Aircore · Collar locations were initially surveyed using A mobile phone GPS utilising the Avenza Map app. Collar points recorded with a horizontal accuracy within 5m. · Locations are recorded in geodetic datum GDA 94 zone 53. · No downhole surveying was undertaken on AC or Sonic holes. All holes were set up vertically and are assumed vertical. · Higher accuracy GPS will be undertaken on sonic core drilling to support future resource estimates |
| Appendix 3: Section 2 reporting of exploration results | ||
| Criteria | JORC Code explanation | Commentary |
| Mineral tenement and land tenure status | · Type, reference name/number, location and ownership including agreements or material issues with third parties such as joint ventures, partnerships, overriding royalties, native title interests, historical sites, wilderness or national park and environmental settings. · The security of the tenure held at the time of reporting along with any known impediments to obtaining a licence to operate in the area. | · Boland is located on EL5953, currently owned 100% by Peninsula Resources limited, a wholly owned subsidiary of Andromeda Metals Limited. · In 2024, Cobra through its subsidiary Lady Alice Mines purchased the remaining ownership of the Wudinna Project tenements. · An application through partial surrender is currently with the South Australian Government which will see LAM as the 100% owner of areas of the Wudinna Project. · Alcrest Royalties Australia Pty Ltd retains a 1.5% NSR royalty over future mineral production from licenses EL6001, EL5953, EL6131, EL6317 and EL6489. · A Native Title Agreement is in place with the Barngarla people. · Aboriginal heritage surveys have been completed over EL5953, with no sites located in the immediate vicinity of aircore drilling |
| Geology | · Deposit type, geological setting and style of mineralisation. | · Target mineralisation is ionic rare earth mineralisation that occurs primarily within the Pidinga Formation within the Narlaby Palaeochannel, immediately above REE enriched Hiltaba Suite Granites · Ionic REE mineralisation also occurs in and adjacent to the Garford formation clays and silty sands. · Significant chemical (pH & eH) differences exist between underlying saprolite and overlying Palaeochannel sediments. REEs are absorbed to reduced organics found within the Pidinga Formation · Benchtop metallurgy studies indicate ISR amenability of rare earths within the Pidinga Formation basal sands summarized in RNS 1285Q (16 December 2024) · Ionic REE mineralisation is confirmed through metallurgical desorption testing where high recoveries are achieved at benign acidities (pH4-3) at ambient temperature. · QEMSCAN and petrology analysis support REE ionic mineralisation, with little to no secondary phases identified. · Ionic REE mineralisation occurs in reduced clay intervals that contact both saprolite and permeable sand units. Mineralisation contains variable sand quantities that yield permeability and promote in-situ recovery potential · Mineralisation is located within a confined aquifer |
| Data aggregation methods | · In reporting Exploration Results, weighting averaging techniques, maximum and/or minimum grade truncations (eg cutting of high grades) and cut-off grades are usually Material and should be stated. · Where aggregate intercepts incorporate short lengths of high grade results and longer lengths of low grade results, the procedure used for such aggregation should be stated and some typical examples of such aggregations should be shown in detail. · The assumptions used for any reporting of metal equivalent values should be clearly stated. | · Reported summary intercepts are weighted averages based on length. · No maximum/ minimum grade cuts have been applied. · No metal equivalent values have been calculated. · Rare earth element analyses were originally reported in elemental form and have been converted to relevant oxide concentrations in line with industry standards. Conversion factors tabulated below: Element Oxide Factor Cerium CeO2 1.2284 Dysprosium Dy2O3 1.1477 Erbium Er2O3 1.1435 Europium Eu2O3 1.1579 Gadolinium Gd2O3 1.1526 Holmium Ho2O3 1.1455 Lanthanum La2O3 1.1728 Lutetium Lu2O3 1.1371 Neodymium Nd2O3 1.1664 Praseodymium Pr6O11 1.2082 Scandium Sc2O3 1.5338 Samarium Sm2O3 1.1596 Terbium Tb4O7 1.1762 Thulium Tm2O3 1.1421 Yttrium Y2O3 1.2699 Ytterbium Yb2O3 1.1387 · The reporting of REE oxides is done so in accordance with industry standards with the following calculations applied: · TREO = La2O3 + CeO2 + Pr6O11 + Nd2O3 + Sm2O3 + Eu2O3 + Gd2O3 + Tb4O7 + Dy2O3 + Ho2O3 + Er2O3 + Tm2O3 + Yb2O3 + Lu2O3 + Y2O3 · LREO = La2O3 + CeO2 + Pr6O11 + Nd2O3 · HREO = Sm2O3 + Eu2O3 + Gd2O3 + Tb4O7 + Dy2O3 + Ho2O3 + Er2O3 + Tm2O3 + Yb2O3 + Lu2O3 + Y2O3 · MREO = Nd2O3 + Pr6O11 + Tb4O7 + Dy2O3 · NdPr = Nd2O3 + Pr6O11 · TREO-Ce = TREO - CeO2 · % Nd = Nd2O3/ TREO · % Pr = Pr6O11/TREO · % Dy = Dy2O3/TREO · % HREO = HREO/TREO · % LREO = LREO/TREO · XRF results are used as an indication of potential grade only. Due to detection limits only a combined content of Ce, La, Nd, Pr & Y has been used. XRF grades have not been converted to oxide. |
| 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. | · REE mineralization occurs in several phases, primary phase mineralisation occurs within the Pidinga Formation which is amenable to ISR recovery and the Garford Formation, REO values within both of these formations have been reported. Mineralisation occurring within the saprolite is considered secondary phase mineralisation. · The results reported in this announcement are of a research and development nature, further tests are planned that will enable the company to better evaluate the commercial viability and economic potential of cerium removal to be incorporated into its flowsheet. |
| 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. | · ISR study 1 was performed to achieve a pH 3 whilst ISR study 2 was performed at a pH of 3. · Results from the most recent 55kg composite column were performed at 0.3M pH3 · Future metallurgical testing will focus on producing PLS under leach conditions to conduct downstream bench-scale studies for impurity removal and product precipitation. · Hydrology, permeability and mineralogy studies are being performed on core samples. · Installed wells are being used to capture hydrology base line data to support a future infield pilot study. · Infield studies support ISR recovery of REEs · Trace line tests shall be performed to emulate bench scale pore volumes. |
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