Patagonia Lithium Formentera Well 7 Brine Results Signal MRE Expansion

Patagonia Lithium's Well 7 Delivers Standout Brine Results, Setting Up MRE Expansion at Formentera

Patagonia Lithium Ltd (ASX: PL3) has announced a significant operational milestone at its Formentera Lithium Project in Argentina's Jujuy Province, with Patagonia Lithium Formentera Well 7 brine results delivering high-quality brine extraction outcomes that the company says augur well for pumping and a potential expansion of its existing Mineral Resource Estimate (MRE).

The well has now reached 350 metres depth, with 11 of 13 packer assay tests completed successfully, each extracting 200 litres of brine for laboratory analysis. Meanwhile, Wells 1, 2, 3, and 4 are underway on 72-hour pump tests, with surrounding wells being monitored for brine level changes — a standard process for understanding aquifer connectivity and resource continuity.

The Numbers That Matter: Brine Quality Metrics From Test 11

The results from the 11th packer test at 332 metres depth are the headline figures from this announcement. Industry benchmarks for lithium brine quality are well established, and Well 7's readings exceed them across the board.

These readings confirm that the brine being extracted at depth is mineral-rich and of high concentration, a strong early indicator of economic potential in lithium brine projects.

Executive Chairman Phillip Thomas said: "We are achieving great results on the packer tests with flow rates of 200–857 litres per hour, that augurs well for pumping. This large sandstone unit with high porosity and a clay aquitard above it is great structure and will allow lithium to concentrate. These porosity results mean our MRE domain is expected to be expanded and will contribute to additional volume, as we now have each corner of the concession drilled."

Understanding Lithium Brine Geology: Why These Results Matter

What Is a Packer Test?

A packer test is a method used in brine drilling where an inflatable device (the "packer") seals off a specific section of the well, allowing engineers to extract and measure brine from a precise depth interval. This enables accurate sampling of distinct aquifer zones rather than mixing fluids from multiple depths.

Why Does the Geology at Well 7 Matter?

The structural picture emerging from Patagonia Lithium Formentera Well 7 brine results is particularly encouraging. Several key geological features reinforce the project's potential:

• The interval between 281–341 metres consists of semi-consolidated to unconsolidated brown medium to fine sands, with 80% quartz, 15% lithics, and 5% opaque minerals, showing moderate to high visual porosity
• Core samples between 270–293 metres reveal gravels and sands contributing to high porosity — the physical void space that allows brine to accumulate and flow
• Critically, a clay aquitard sits above this high-porosity zone, acting as a seal and preventing lower-quality brines from mixing downward and diluting the lithium-rich brine below
• Angular gravel clasts indicate high-energy depositional conditions, consistent with coarse, permeable sediment sequences that host productive lithium brine aquifers
• The sequence is described as a regionally connected distal sandy system, with volcaniclastic sandy levels affected by iron-oxide enrichment, interpreted as indicative of lithium-bearing minerals

Understanding Lithium Brine Projects: Key Concepts Explained

For investors less familiar with brine geology, the following terms are central to evaluating these results:

• Aquitard: A geological layer of low permeability that restricts brine movement, helping concentrate lithium-rich fluids in adjacent permeable zones
• Porosity: The percentage of void space in a rock or sediment that can hold fluid; higher porosity generally means greater brine storage capacity
• Electrical Conductivity (EC): A proxy measure of dissolved mineral content; higher EC values correlate with greater concentrations of dissolved salts, including lithium
• Specific Gravity (SG): The density of a fluid relative to water; brines with SG above 1.10 are considered lithium-rich in Andean salar projects
• TDS (Total Dissolved Solids): The combined content of all inorganic and organic substances in a brine; a higher TDS value indicates a more mineralised solution

Project Context: Building Toward an Expanded MRE

This announcement does not exist in isolation — it builds on a track record of progressive drilling results at Formentera since Patagonia Lithium listed on the ASX in March 2023. Furthermore, the breadth of milestones achieved to date underscores the systematic nature of the company's exploration approach.

Drilling History and Key Milestones at Formentera

1. Surface sampling and MT (magnetotelluric) geophysics completed across the project area
2. Drill holes JAM-24-01 through JAM-24-04 completed, with assay results including 591 ppm lithium in JAM-24-01
3. Historical surface samples as high as 1,122 ppm Li recorded at Formentera
4. Very low resistivities recorded to more than 1 km depth during the MT geophysics survey, indicating large-scale brine presence at depth
5. JAM 25-05 and JAM 26-06 completed prior to the current well
6. On 14 July 2025, an upgraded MRE was released at 551,000 tonnes LCE — representing a 319% increase over the prior estimate
7. JAM 26-07 now at 350 metres, projected to reach 600 metres

The current MRE stands as follows:

With Patagonia Lithium Formentera Well 7 brine results now drilling at the corner of the concession and delivering high-porosity, high-conductivity outcomes, the MRE domain is expected to be expanded following completion of the planned BMR gamma porosity survey and 72-hour pump test on this well.

What Lithium Carbonate Equivalent (LCE) Means for Investors

LCE represents the standard unit used to report lithium resource estimates, reflecting the equivalent mass of lithium carbonate producible from a given quantity of lithium. This standardisation allows investors to compare projects across different geographic regions and geological settings.

The current resource of 551,400 tonnes LCE at an average grade of 294 mg/L positions Formentera within the range of economically viable lithium brine projects globally. For context, successful lithium brine operations typically target grades above 200 mg/L, making Formentera's results commercially relevant.

Next Steps: What Investors Should Watch For

The company has outlined a clear sequence of near-term activities that will inform the next resource update:

• Completion of packer tests at 375 metres on JAM 26-07 — the next scheduled test depth
• Continuation of drilling toward the projected 600-metre target depth on Well 7
• 72-hour pump tests on Wells 1, 2, 3, and 4 currently underway, with monitoring of brine level changes across adjacent wells to assess aquifer connectivity
• BMR gamma porosity survey proposed prior to a new MRE update
• MRE expansion anticipated following the above work programme, with all four corners of the concession now drilled
• Pilot plant location already proposed near JAM 26-07

The Broader Picture: A Multi-Asset Explorer in the Lithium Triangle

Patagonia Lithium's asset base extends well beyond Formentera. In addition to its flagship project, the company maintains a diversified portfolio across South America and Brazil.

The Brazilian portfolio includes a staked position adjacent to CMOC's Niobium operation — the largest Niobium producer in Brazil — which produces 10,024 tonnes of Niobium per annum.

Investment Considerations: Why Well 7 Results Matter

Several converging factors make Patagonia Lithium Formentera Well 7 brine results and MRE expansion meaningful for investors tracking the company's development trajectory:

• Well 7 is exceeding quality benchmarks — both EC and SG readings from test 11 sit above the thresholds considered "excellent" for Andean lithium brine projects
• Flow rates of 200–857 litres per hour across packer tests indicate productive aquifer zones with practical pumping potential
• The MRE is explicitly flagged for expansion — with all four corners of the concession now drilled and high-porosity zones confirmed
• 72-hour pump tests on four wells simultaneously represent a significant operational step toward understanding production-scale characteristics
• Chain of custody and dual-laboratory protocols (SGS and Alex Stewart, both ISO/IEC 17025:2017 certified) underpin data integrity
• A pilot plant location has already been identified adjacent to JAM 26-07, suggesting the company is thinking beyond exploration toward early-stage production planning

Capital Structure (as at Announcement Date)

• Shares on issue: 207.1 million
• Unquoted options: 20.0 million
• Unquoted performance rights: 25.0 million

Technical Quality Assurance Standards

The company has implemented comprehensive quality control measures that strengthen confidence in the reported results. Both core and brine samples were taken and stored according to chain of control procedures. Samples are tested on-site for conductance using a Hanna multi meter calibrated prior to use with fresh standards.

Field duplicates, standards and blanks are used to monitor potential contamination of samples and the repeatability of analyses. A distilled water sample and a lithium standard sample C 3001 (248 ppm) were supplied to both SGS and Alex Stewart laboratories for quality assurance.

Both laboratories are certified for ISO/IEC Standard 17025:2017, providing independent verification of brine chemistry results that underpin resource calculations.

Key Takeaway: Patagonia Lithium has positioned itself as a credible early-stage lithium brine developer in one of the world's most productive lithium-bearing geological settings. With Patagonia Lithium Formentera Well 7 brine results delivering brine quality that exceeds industry benchmarks, a 551,400-tonne LCE resource base flagged for expansion, and four wells simultaneously under pump test, the next few months represent a meaningful technical de-risking window for the project. Investors following the lithium brine development space should track upcoming assay results, the 72-hour pump test outcomes, and any MRE update announcement closely.

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