Exceptional Metallurgical Results From ISR Column

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.

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14 October 2025

Cobra Resources plc

("Cobra" or the "Company")

Exceptional Metallurgical Results From Large Scale ISR Column

Results indicative of further reduced costs and increased production capacity

Cobra (LSE: COBR), a South Australian mineral exploration and development company, is pleased to announce highly favourable results from metallurgical studies on a large 55kg column sample from the Boland Ionic Rare Project ("Boland") subjected to in situ recovery ("ISR") conditions. The tests were carried out in collaboration with the Australian Nuclear Scientific Technology Organisation ("ANSTO").

Highlights

·    Rapid recoveries enabled by high permeabilities - a highly favourable orebody characteristic for ISR

·    In just 17 days, the study achieved the following favourable results using 0.3 molar, (NH₄)₂SO₄ AMSUL targeting pH3:

·    68% Terbium (Tb)

·    63% Dysprosium (Dy)

·    62% Samarium (Sm)

·    57% Neodymium (Nd)

·    51% Praseodymium (Pr)

All achieved at very low acid consumption of just 3.88 kg/t

·    Recoveries are from a 55kg bulk composite sample taken from intervals of mineralisation from three sonic core holes yielding a head grade of 1,194ppm TREO (252ppm Nd+Pr and 33pm Dy +Tb)

·    Owing to the high permeability of samples, the test was executed at pressure of 2 bar where the average permeability rate was 2.1m/day

·    Post test completion, the pressure was increased to 5 bar, to reflect the Boland aquifer, where a permeability rate of 8.72 m/day was achieved

·    Preparations are underway to perform in-field permeability tests that aim to emulate the permeability rates achieved in this study - regulatory EPEPR approval received; a discharge permit is expected shortly that will enable the commencement of field testing

·    Further testing is ongoing to optimise the flow sheet, with results pending for:

o  Sulphuric acid generation - tests aiming to maximise the natural generation of acid from organic pyrite within the ore body that can materially reduce acid requirements - a primary operating cost of any Rare Earth operation

o  Cerium and Lanthanum reduction from generated pregnant liquor. Cerium is an abundant REE of low value - through additional testing Cobra aims to maximise product payability by maximising the proportions of Dysprosium and Terbium

·    Mixed Rare Earth Carbonate ("MREC") to be produced from the optimised flowsheet - subsequent MREC product to be tested by prospective offtake parties

Rupert Verco, Managing Director of Cobra, commented:

"Christmas has come early with these results; they have confirmed our belief that the permeability of our first bench scale study was impacted by a small quantity of saprolite being incorporated in the sample. As a result, the study took 150 days to achieve 68% recoveries. We have achieved similar recoveries in just 17 days and at a lower molarity. This means reduced costs and increased production capacity.

From a recovery standpoint, we now have complete confidence in the ionic recoverability of Boland ore and it's now up to the team to demonstrate the ISR process in the field. Should we replicate these permeabilities in field testing, the commercial, environmental and strategic benefits of the Boland discovery will be undisputable.

We are looking forward to completing the acquisition of tenements EL6742, 6774 and 6780 so resource focused drilling can continue to demonstrate the significant scale of the opportunity that aims to deliver low-cost and sustainable critical minerals over a multi-generational mine life.

Updated Chinese export restrictions highlight the need for cost effective, reliably sourced heavy rare earths enabling emerging supply chain resilience. Cobra is advancing a strategy to address market needs for a sustainably sourced, refined heavy rare earth carbonate and the results of this study highlight the Boland Project's ability to meet this demand."

Scaled ISR Testing Results

·    Testing of (NH₄)₂SO₄ "AMSUL" diagnostic leaches below the industry standard of 0.5 molar (M) highlight that acid requirements can be even further reduced by lowering the lixiviant molarity. The completed column test used a diluted acidity of 0.3M targeting a pH endpoint of pH3

Due to the highly permeable nature of the sample, the increase in acidity occurred rapidly, reducing the column's pH to ~4.1 where it stabilised. An increase in the acid dosage took the pH beyond the final set point before levelling out at pH3

·    REE recovery commenced almost instantly with 11.1% of REEs recovered before the acidity dropped below pH 4.1. Recoveries increased rapidly once the column pH reduced (increased acidity) below pH4

Figure 1. Graphed cumulative recoveries from the column over 17 days with associated acidity

Figure 2: ISR column setup containing 55kg of Boland ore

Study results support favourable projects economics with:

·    Very high recovery of valuable and strategically important Heavy Rare Earths ("HREO") being 66.3% achieved using a low molarity 0.3M pH3 AMSUL lixiviant

·    Rapid recoveries enabled with high permeabilities which is a catalyst of ISR productivity

·    Very low acid consumption of 3.88 kg/t which is a significant reduction from the 15 kg/t used in the previous high grade ISR column

·    Breakdown of pyrite during the ISR process contributes to acidity. Owing to this unique trait for an ionic REE orebody, further tests are underway to determine how much acid can potentially be generated through ISR. Results anticipated soon

·    Low levels of radionuclides and impurities recovered, making impurity removal simple and cost effective

Table 1: Full results of ISR column test

Recoveries exceeding 100% are a result of ground water salinity contributing to the overall quantity of Ca, Mg and Na

Next Steps

The purpose of this ISR column has been to:

1.    Validate the permeability achieved in previous tests at a greater scale

2.    Optimise an already low-cost flowsheet that produced a high grade MREC by:

a.    Maximising the proportion of Dysprosium and Terbium in the final product

b.    Reducing the quantity of low value REEs: Ce and La

c.     Reducing the quantity of acid required

3.    Produce adequate MREC for offtake analysis

4.    Provide confidence to metallurgical inputs into economic analysis

Following this successful testwork, the following next steps outline the Boland workstreams and anticipated timeframes:

Metallurgical Optimisation:

·    Acid generation studies aimed at reducing the acid required to recover REEs: 1-2 weeks

·    Ce and La reduction: 2-3 weeks

·    Impurity removal: 3-4 weeks

·    Product quality: 4-6 weeks

·    Outcomes of offtake testing: 3-12 months

Field Studies:

·    Pump and tracer permeability studies: Planned to commence later this month once the final discharge permit is received, results within 3-6 weeks

·    Infield pilot study: 6-12 months

·    Environmental baseline and impact assessments: ongoing

Tristar Acquisition

·    Transfer of Native Title Mining Agreement (NTMA) - in process

·    Transfer of Tenure (Acquisition completion) (contingent upon the above) - Expected to take 1-3 months

·    EPEPR Submission (contingent upon the above) - Expected to take 1-2 months

Resource & Project Economics

·    Boland extensional drilling (late November - December)

·    Regional Drilling (contingent upon the completion of the TriStar acquisition)

Boland Project

At Boland, Cobra has discovered what it believes to be a unique, scalable instance where ionic rare earth elements - containing economically attractive grades of valuable heavy and magnet rare earths - occur in a permeable horizon confined between horizons of impermeable clay.

Bench scale ISR testing has confirmed that this mineralisation is amenable to ISR recovery techniques. ISR techniques are currently in use (and have been used successfully for decades) in geologically similar environments, to recover uranium in South Australia which maintains a well-established ISR regulatory system.

Results of Cobra's ongoing mineral recovery test work indicate that, with minor optimisation, ISR techniques will enable non-invasive and low-cost production of critical REEs from its discovery at Boland.

Follow this link to watch a short video of CEO Rupert Verco explaining the results released in this announcement: https://investors.cobraplc.com/link/PGqZle

Further information relating to Boland and these results are presented in the appendices.

Enquiries:

The person who arranged for the release of this announcement was Rupert Verco, Managing Director of the Company.

Information in this announcement relates to exploration results that have been reported in the following announcements:

·    Exploration update: "Met Study Supports Even Lower-Cost Recoveries", dated 11^th September 2025

·    Exploration update: "Low-Cost Recoveries from Optimised Testing", dated 11^th August 2025

·    Exploration update: "Rare Earth ISR System beyond Boland", dated 4^th August 2025

·    Exploration update: "Favourable Boland Metallurgical Results", dated 21st July 2025

·    Exploration update: "Boland Project Update", dated 26^th June 2025

·    Wudinna Project Update: "Boland Aircore Drill Results", dated 25^th February 2025

·    Wudinna Project Update: "Further Positive Metallurgy Results from Boland Project", dated 16 December 2024

·    Wudinna Project Update: "2^nd Bench Scale ISR Study & £1.7M Placing", dated 26 November 2024

·    Wudinna Project Update: "ISR Bench Scale Study Completion", dated 4 November 2024

·    Wudinna Project Update: "ISR bench scale study delivers exceptional results", dated 1 October 2024

·    Wudinna Project Update: "ISR bench scale update - Exceptionally high recoveries with low impurities and low acid consumption; on path to disrupt global supply
of heavy rare earths", dated 28 August 2024

·    Wudinna Project Update: "ISR bench scale update -Further metallurgical success at world leading ISR rare earth project", dated 11 July 2024

·    Wudinna Project Update: "ISR bench scale update - Exceptional head grades revealed", dated 18 June 2024

·    Wudinna Project Update: "Re-Assay Results Confirm High Grades Over Exceptional Scale at Boland", dated 26 April 2024

Competent Persons Statement

The information in this report that relates to metallurgical results is based on information compiled by Cobra Resources and reviewed by Mr James Davidson who is Principal at Rendement and a Fellow of the Australian Institute of Mining and Metallurgy (FAusIMM). Mr Davidson has sufficient experience that is relevant to the metallurgical testing which was undertaken to qualify as a Competent Person as defined in the 2012 edition of the "Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves". Mr Davidson consents to the inclusion in this report of the matters based on this information in the form and context in which it appears.

Information in this announcement has been assessed by Mr Rupert Verco, a Fellow of the Australasian Institute of Mining and Metallurgy. Mr Verco is an employee of Cobra and has more than 17 years' industry experience which is relevant to the style of mineralisation, deposit type, and activity which he is undertaking to qualify as a Competent Person as defined in the 2012 Edition of the Australasian Code for Reporting Exploration Results, Mineral Resources and Ore Reserves of JORC. This includes 13 years of Mining, Resource Estimation and Exploration.

About Cobra

Cobra Resources is a South Australian critical minerals developer, advancing assets at all stages of the pre-production pathway.

In 2023, Cobra identified the Boland ionic rare earth discovery at its Wudinna Project in the Gawler Craton - Australia's only rare earth project suitable for in situ recovery (ISR) mining. ISR is a low-cost, low-disturbance extraction method that eliminates the need for excavation, positioning Boland to achieve bottom-quartile recovery costs.

In 2025, Cobra further expanded its portfolio by optioning the Manna Hill Copper Project in the Nackara Arc, South Australia. The project contains multiple underexplored prospects with strong potential to deliver large-scale copper discoveries.

In 2025, Cobra sold its Wudinna Gold Assets to Barton Gold (ASX: BDG) for up to A$15 million in cash and shares.

Regional map showing Cobra's tenements in South Australia

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Appendix 1: Background information - the Boland Project and ISR

·    The Boland Project was discovered by Cobra in 2023. Mineralisation is ionically bound to clays and organics within palaeochannel sands within the Narlaby Palaeochannel

·    Mineralisation occurs within a permeable sand within an aquifer that is saltier than sea water and is confined by impermeable clays

·    ISR is executed through engineered drillhole arrays that allow the injection of mildly acidic ammonium or magnesium sulphate lixiviants, using the confining nature of the geology to direct and lower the acidity of the orebody. This low-cost process enables mines to operate profitably at lower grades and lower rates of recovery

·    Once REEs are mobile in solution in groundwater, it is also possible, from an engineering standpoint, to recover the solution to surface via extraction drillholes, without any need for excavation or ground disturbance

·    The capital costs of ISR mining are low as they involve no material movements and do not require traditional infrastructure to process ore - i.e. metals are recovered in solution

·    Ionic mineralisation is highly desirable owing to its high weighting of valuable HREOs and the cost-effective method in which REEs can be desorbed

·    Ionic REE mineralisation in China is mined in an in-situ manner that relies on gravity to permeate mineralisation. The style of ISR process is unconfined and cannot be controlled, increasing the risk for environmental degradation. This low-cost process has enabled China to dominate mine supply of HREOs, supplying over 90% globally

·    Confined aquifer ISR is successfully executed globally within the uranium industry, accounting for more than 60% of the world's uranium production. This style of ISR has temporary ground disturbance, and the ground waters are regenerated over time

·    Cobra is aiming to demonstrate the economic and environmental benefits of recovering ionic HREOs through the more environmentally aquifer controlled ISR - a world first for rare earths

Figure A1: Comparison between the Chinese and the proposed Boland process for ISR mining of REEs

Appendix 2: Metallurgical sample information

Appendix 3: JORC Code, 2012 Edition - Table 3

Appendix 4: Section 2 reporting of exploration results