Patagonia Lithium has completed drilling its Formentera well to 488 metres, intersecting promising lithium-bearing brines and porous sediments. Early tests suggest strong flow rates and increasing lithium concentrations, setting the stage for resource upgrades.
- Well JAM 26-06 drilled to 488m, intersecting porous sandy sediments
- Packer tests show strong flow rates and increasing lithium brine concentration
- Samples sent to accredited labs for assay analysis
- Results correlate with previous wells, supporting aquifer domain extension
- Further testing including 72-hour pump test and porosity surveys planned
Drilling Progress and Geological Insights
Patagonia Lithium Ltd (ASX – PL3) has announced the successful completion of drilling at its Formentera concession in Argentina, reaching a depth of 488 metres with Well JAM 26-06. The drilling intersected a sequence of sandy and silty sediments exhibiting high porosity, particularly between 80-200 metres and 340-400 metres, which are promising zones for lithium-bearing brines. The well also encountered a hard claystone mudrock unit known as the Vizcachera Formation, dating back approximately 14 million years, which acts as a non-porous barrier within the stratigraphy.
Encouraging Preliminary Test Results
Eight out of nine packer tests conducted during drilling successfully pumped brine samples, with infield measurements indicating a rising trend in specific gravity and electrical conductivity, both proxies for dissolved lithium and other elements. Notably, at 420 metres depth, the specific gravity reached 1.13 gm/cm³, up from 1.02 gm/cm³ in shallower zones, while electrical conductivity hit the upper limit of the measuring device at 200 mS/cm. These results suggest increasing concentrations of lithium and other dissolved ions in the brines.
Laboratory Assays and Next Steps
Samples from the packer tests have been dispatched to two accredited laboratories, Alex Stewart and SGS, for detailed assay analysis, including lithium concentration and porosity testing. Core samples extracted near the bottom of the hole will undergo further laboratory evaluation to assess porosity and total yield, critical parameters for resource estimation. The company is preparing for an extended 72-hour pump test to better understand flow rates and aquifer characteristics, while slotted PVC casing installation and Borehole Magnetic Resonance (BMR) surveys are planned to refine porosity measurements.
Strategic Implications and Resource Potential
Executive Chairman Phillip Thomas highlighted the significance of the well’s results, noting strong correlations with previous drilling at nearby wells JAM 25-05 and JAM 24-02. This continuity supports confidence in extending the aquifer domains and advancing the Mineral Resource Estimate (MRE) towards an indicated status. Patagonia Lithium’s recent MRE upgrade in July 2025 already reported a 319% increase in lithium carbonate equivalent, underscoring the project’s growing scale and potential.
Broader Project Context
Patagonia Lithium operates two major lithium brine projects in Argentina’s lithium triangle, the Formentera/Cilon project in Jujuy Province and the Tomas III project in Salta Province, as well as exploration concessions in Brazil targeting ionic rare earth element clays and lithium pegmatites. The Formentera project’s promising drilling results come amid a global push to secure lithium supply chains for electric vehicle batteries and energy storage.
Bottom Line?
With drilling success and promising early data, Patagonia Lithium is poised to advance its resource base and attract market attention as assay results come in.
Questions in the middle?
- What will the final lithium concentrations from lab assays reveal about economic viability?
- How will the upcoming 72-hour pump test refine understanding of aquifer productivity?
- Which new well sites will Patagonia select to upgrade resource classification to indicated status?