IRIS is now only the second ASX-listed hard rock lithium explorer in the US, after completing the acquisition of White Rock and its intriguing South Dakota project.

The company had selected the 10,846 acre project, which comprises the Dewy and Custer sub-projects, in the Black Hills region of South Dakota after assessing several projects.

While both Dewy and Custer sub-projects already cover large areas of fertile lithium-cesium-tantalum (LCT) pegmatites covering several historical lithium mines and numerous historical industrial mineral pegmatite mines, IRIS Metals (ASX:IR1) is also moving to stake out additional areas of interest following a review of regional geology.

“The securing of the highly prospective tenure in a globally significant jurisdiction through the completion of the White Rock acquisition is transformational to IRIS,” chairman Simon Lill says.

“It diversifies the company geographically and by commodity, providing shareholders with exposure into the highly strategic battery metals space.

“The US in general and South Dakota specifically present a supportive environment for the development of battery metals assets; leaving IRIS ideally positioned to leverage from exploration success.

“We look forward to commencing work and keeping the market informed of our progress.”

US President Joe Biden’s recent invoking of the Defense Production Act is poised to light a fire under US lithium projects, by supporting and encouraging the domestic production of strategic metals.

IRIS has established a geology team which is currently on site undertaking pegmatite mapping, rock chip sampling and planning an initial exploration program.


South Dakota Lithium

The Black Hills region is 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 sub-project hosts the historical Hunter and Louise mine, which comprises 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.

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

Custer includes 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.

More recently, director Chris Connell’s due diligence visit included field work supported by the use of a Laser-Induced Breakdown Spectroscopy analyser, which can assist with the recognition of spodumene from lithium pegmatite ores.

This work and other geological reference materials led the company to decide on expanding its South Dakota footprint by staking further claims that are considered to be strategic, complementary and accretive to its current tenure.

Connell is currently in transit to South Dakota to supervise this program, as well as direct the geological team currently on site in its pegmatite mapping and rock chip sampling activities.

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.