Lower Lithium Concentrations in Formentera Well JAM 25-05 Highlight Need for Further Drilling and Analysis

Exploration Results from Well JAM 25-05

Patagonia Lithium Ltd (ASX:PL3) has released results from its recent drilling and core analysis at Well JAM 25-05, part of the Formentera Lithium Project located in the Salar de Jama region of Jujuy Province, Argentina. The company reported that core samples exhibited effective, total, and specific yield porosity values ranging from 17% to 28.7%, which are notably above the local regional average. Drainable porosity measured at 5 psi pressure ranged between 9.05% and 18.03%, indicating that brine can flow with relatively low pumping effort.

Brine samples taken at depths of 99-102m, 132-133.5m, and 165-170m assayed lithium concentrations of 156ppm, 195ppm, and 219ppm respectively. These values are lower than the 580ppm lithium assays reported from earlier wells at the project but nonetheless contribute to the understanding of the aquifer’s extent and quality.

Implications for Mineral Resource Estimate

Executive Chairman Phillip Thomas commented that the porosity results are significant as they suggest a larger aquifer domain, potentially expanding the Mineral Resource Estimate (MRE) for the project. The current MRE, lodged in July 2025, stands at 551,400 tonnes of lithium carbonate equivalent (LCE) at an average grade of 294mg/L lithium, comprising 14,800 tonnes LCE indicated and 536,600 tonnes LCE inferred.

The company confirmed that there is no new information materially affecting the assumptions or technical parameters underpinning the existing MRE. However, the new porosity and lithium assay data from Well JAM 25-05 may complement previous results and support future updates to the resource estimate.

Technical Details and Methodology

The drilling was conducted using a Boart Longyear LT190 core rig to a depth of 401m, with core recovery exceeding 95%. Brine samples were collected using a packer air lift system at specified intervals and analysed by accredited laboratories Alex Stewart and SGS, both certified to ISO/IEC Standard 17025:2017. Quality control measures included duplicate sampling, insertion of blanks and standards, and chain of custody protocols.

Porosity measurements employed the Relative Brine Release Calculation (RBRC) test, a standard technique in lithium exploration that assesses potential porosity and permeability in brine reservoirs. Capillary pressure curves indicated that most production pumps, which operate below 50 psi, would be effective in extracting brine from the aquifer.

Next Steps and Broader Project Context

Patagonia Lithium plans to conduct further drilling, seismic surveys, and gamma porosity studies to better define the resource and update the MRE. The Formentera project is one of two major lithium brine projects held by the company in northern Argentina, alongside the Tomas III project in Salta Province. The company also holds exploration concessions in Brazil targeting ionic rare earth element clays and lithium in pegmatites.

Recent coverage has highlighted strong pump test results and higher lithium assays from other Formentera wells, such as JAM 26-06, which reported assays up to 412ppm lithium and robust flow rates. These developments collectively contribute to the evolving understanding of the project’s potential.