IRIS Metals is acquiring a hard rock lithium project in South Dakota that has an abundance of mapped pegmatites and historical lithium-bearing mines.

The acquisition of the 10,846 acre project, which comprises the Dewy and Custer sub-projects, is incredibly well-timed given US President Joe Biden’s recent move to invoke the Defense Production Act to encourage domestic production of battery metals.

IRIS Metals (ASX:IR1) selected the South Dakota project after assessing several projects and has raised $2m through a placement to support the acquisition and provide working capital for initial exploration.

“After methodically assessing numerous projects to complement our suite of Australian assets, the board has achieved an agreement that has met its key investment criteria of geographic and commodity diversification in a mining friendly jurisdiction,” executive director, Tal Paneth says.

“The acquisition of the highly prospective hard rock lithium South Dakota Project sees IRIS join the green battery revolution at a time when the US President has recently enacted legislation to encourage domestic lithium production.”

Non-executive director Chris Connell, who spent six weeks assessing the project, said it includes townships in the Black Hills of South Dakota that were founded on mining and had a long, proud history of supporting local mining operations – including lithium.

Going deep in South Dakota

The Black Hills of South Dakota are known for historical lithium mining dating back to 1898 when lithium-bearing spodumene with up to 8% lithium oxide and amblygonite containing up to 10% lithium oxide were first mined near the township of Custer.

Other economic minerals mined in the area include gold – like the 40Moz Homestake gold mine, beryl, columbite-tantalite, mica, feldspar, quartz and tin.

The Dewy and Custer sub-projects represent large areas of fertile lithium-cesium-tantalum (LCT) pegmatites covering several historic lithium mines and numerous historical industrial mineral pegmatite mines.

At Dewy, the historical Hunter and Louise mine is composed of six small open cut pits that were primarily mined for mica and spodumene. The mineralised pegmatite is exposed at surface for over 200m with varying widths averaging 10m.

Meanwhile, the Tin Queen mine that consists of three open cut pits, commenced operations in the early 1940’s and has operated intermittently since then.

While it initially targeted tin, later production focused primarily on mica with amblygonite and beryl recovery. Other lithium minerals at the mine include spodumene and lithiophilite-triphylite.

Custer hosts the Custer Mountain mine that was mined for feldspar and beryl sporadically since 1942, while mapping of the mine by the US Geological Survey in 1945 described pegmatite zones rich in spodumene, amblygonite and lepidolite.

Exploration Plans

IRIS’ initial exploration work will consist of mapping, gridded soil and rock chip sampling to determine the priority targets for drill testing.

To assist with its initial evaluation, the company has acquired a Laser-Induced Breakdown Spectroscopy (LIBS) analyser that provides real time and in-field analysis as to the presence of lithium within the host medium.

This is expected to help the company rapidly identify the highest priority target areas, prior to an in-depth geochemical and subsequent drill program.

This article was developed in collaboration with IRIS Metals, 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.