Drilling Advances at Formentera: What Risks Lurk Beneath the Lithium Brines?
Patagonia Lithium has reported successful initial brine extraction and core sampling at its Formentera lithium project in Argentina, marking steady progress in its drilling campaign. Early results indicate favorable porosity and brine characteristics that support ongoing exploration efforts.
- First packer brine extraction test at 98-104m depth completed successfully
- Brine samples show good specific gravity and conductivity, indicating lithium potential
- Core samples reveal highly porous sands conducive to lithium concentration
- Drilling reached 119m with plans to extend to 600m depth
- No material changes to the existing Mineral Resource Estimate of 551,400 tonnes LCE
Steady Progress at Formentera
Patagonia Lithium Ltd (ASX, PL3) has announced encouraging results from its ongoing drilling program at the Formentera concession in the Salar de Jama, northern Argentina. The latest well, JAM 25-05, reached a depth of 119 metres as of late November 2025, with the first packer brine extraction test successfully conducted between 98 and 104 metres.
The test yielded a flow rate of approximately 1,286 litres per hour, filling five 150-litre containers in about seven minutes each. The brine sample exhibited a specific gravity of 1.055 gm/cm³ and conductivity of 85.7 mS/cm, both positive indicators for lithium brine quality, alongside a slightly alkaline pH of 7.95 and a temperature of 12.63°C.
Geological Insights and Core Analysis
Core samples extracted from the well reveal predominantly clast-supported medium brown sands with subrounded quartz and sandstone clasts, known for their high porosity. This porosity is critical as it facilitates the concentration and flow of lithium-rich brines. The geological setting suggests a high-energy clastic depositional environment, with evidence of evaporitic diagenesis indicated by gypsum crystals and chlorite-type alteration minerals.
Phillip Thomas, Executive Chairman, highlighted the encouraging nature of the core samples and the expectation that lithium concentrations will increase with depth, as observed in previous wells. The company is awaiting laboratory porosity analyses and detailed lithium assays from two independent labs, SGS and Alex Stewart, to validate these early findings.
Ongoing Exploration and Resource Confidence
The drilling campaign is progressing on schedule and budget, with plans to extend the well to a projected depth of 600 metres and conduct further packer tests at deeper intervals. Patagonia Lithium confirmed no material changes to its July 2025 Mineral Resource Estimate, which currently stands at 551,400 tonnes of lithium carbonate equivalent (LCE), including both indicated and inferred resources.
Additional wells and geophysical surveys are planned to refine the resource model and support future updates. The company maintains rigorous sampling and quality control protocols, ensuring data integrity and compliance with JORC reporting standards.
Strategic Positioning in the Lithium Triangle
Patagonia Lithium’s Formentera project is strategically located within the lithium triangle, a globally significant lithium-producing region. The company also holds concessions in Argentina and Brazil, targeting lithium and other critical minerals. The ongoing exploration success at Formentera reinforces Patagonia Lithium’s potential to contribute meaningfully to the lithium supply chain amid growing demand for electric vehicle batteries and energy storage solutions.
Bottom Line?
As Patagonia Lithium deepens its drilling and awaits assay confirmations, the market will watch closely for signs of resource expansion and project viability.
Questions in the middle?
- How will deeper drilling impact lithium concentration and resource estimates?
- What are the timelines for receiving and interpreting full assay results from laboratories?
- How might evolving brine characteristics influence future extraction and processing strategies?
