• Pursuit Minerals first Rio Grande Sur well strikes deeper, high-grade lithium brines at the Maria Magdelena tenement
  • This intersection is well below the currently calculated resource of 251,300t LCE
  • Rig to move to drill next deep diamond hole at the Sal Rio II tenement


Special Report: Pursuit Minerals’ maiden drill program at its Rio Grande Sur lithium brine project could add to the size and grade of the current resource after the first hole returned deeper assays of up to 629mg/L.

This high-grade assay from an interval of 512.75m to 518m is just one of several intersections grading above 600mg/L (milligrams per litre of lithium) that were intersected below the currently calculated resource of 251,300t of lithium carbonate equivalent grading 351mg/L.

It follows the intersection of high lithium grades of up to 620mg/L at shallow depths.

Pursuit Mineral’s (ASX:PUR) Rio Grande Sur project sits within Argentina’s Salta province, part of South America’s Lithium Triangle – the world’s largest source of lithium from salt flats.

It is next door to established operations and developments such as Arcadium Lithium’s (ASX:LTM) El Fenix and Sal de Vida, POSCO’s Sal de Oro and Ganfeng’s Mariana projects, among others.

The company’s pilot plant has also started the first phase of operations to produce lithium carbonate using synthetic brine.


Proposed Stage 1 drill holes. Pic: Pursuit Minerals


Deeper, higher-grade lithium

PUR’s maiden six-hole Stage 1 drill program is now off to a great start with the first hole – DDH1 on the Maria Magdelena tenement – returning substantial high-grade lithium brine intersections below the existing resource.

Additionally, the company noted that its on-site geologists and drilling team were extremely encouraged by the geological units encountered across the depths of the hole.

This includes a highly porous sandy unit at a depth of ~100-130m that features lithium brine grades substantially above expectations based on historical results. This includes 2m grading 620mg/L from 115.5m.

As such, this zone has been earmarked as the potential location of a pumping well due to its heightened porosity and average grade of 620mg/L.

“The results from DDH-1 are substantial as we demonstrate the world class potential of the Rio Grande Sur project,” managing director Aaron Revelle said.

“With completion of DDH-1, we are continuing the important advancements we have made in our understanding of the RGS project mineralisation, with the results continuing to demonstrate the potential large scale of the project.

“With outstanding high grade brine intercepts of ~600mg/L at depths of 115.5m and those grades continuing to ~520m, the project is exceeding our expectations.

“We continue to progress with permitting for the drilling program in the north of the Rio Grande Sur project, which we intend to include in our Stage 1 program works as we target a substantial mineral resource upgrade.

“This is in addition to works at our lithium carbonate pilot plant which remains on track to produce our first lithium carbonate in the coming months, with Pursuit advancing off-take discussions with multiple requests for product samples from potential off-take partners.”


Next steps

With completion of DDH-1, the onsite drilling crew will now relocate and mobilise to DDH-2 on the Sal Rio II tenement southwest of the Rio Grande Salar.

A transient electromagnetic survey conducted at the salt lake in 2023 outlined a ~100m thick low resistivity (high conductivity) layer from ~150m to 300m depth underlying the tenement.

This high conductivity layer is considered highly prospective for lithium bearing brines.

DDH-2 is expected to be drilled to depths of 500-600m below the surface, consistent with DDH-1, where drilling was substantially deeper than the currently defined JORC resource.

PUR also intends to use brine produced from the Stage 1 drill program at the pilot plant to produce lithium carbonate.



This article was developed in collaboration with Pursuit Minerals, a Stockhead advertiser at the time of publishing.


This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.