IRIS Metals Unveils High-Grade Lithium at Edison, Boosting US Supply Ambitions

Early Drilling Success at Edison

IRIS Metals Limited (ASX – IR1) has announced encouraging initial results from its Phase I diamond drilling program at the Edison Project in South Dakota. The program, which completed 15 drill holes totaling 2,278 meters, has confirmed the presence of high-grade lithium mineralisation within spodumene-bearing pegmatites. Highlighted intersections include a standout 13.4 meters grading 1.78% lithium oxide (Li2O), with higher-grade zones reaching up to 2.51% Li2O.

This early success is significant given the historical importance of the Edison site, which includes the former Edison Mine, once owned by Thomas Edison himself. The pegmatites identified are structurally complex but remain open at depth and laterally, suggesting that further drilling could substantially expand the known resource.

Strategic ‘Hub & Spoke’ Development Model

IRIS Metals is advancing a ‘Hub & Spoke’ strategy that leverages multiple lithium projects in South Dakota, including the Edison, Beecher, and Tin Mountain projects. Central to this approach is the development of a centralized processing facility designed to optimise costs and accelerate production timelines across the portfolio.

Matt Hartmann, IRIS Metals’ U.S. Operations President, emphasised the strategic importance of these findings, noting that confirming high-grade lithium across multiple projects strengthens the company’s position to meet growing domestic demand. This aligns well with U.S. government initiatives supporting critical mineral supply chains, particularly for electric vehicle battery production.

Next Steps and Upcoming Milestones

With assays pending for 11 of the 15 drill holes, IRIS anticipates receiving full results by the third quarter of 2025. These will inform a Phase II drilling program aimed at testing the lateral and depth extensions of the mineralised pegmatites.

Meanwhile, IRIS is preparing to commence test mining and bulk sampling at the Beecher Project by late June 2025, leveraging its fully permitted mining status to demonstrate operational capability. Additional drilling is also planned at the Tin Mountain Project to advance towards a maiden Mineral Resource Estimate, expected in early 2026.

Beyond exploration, the company continues to evaluate acquisition opportunities within South Dakota to bolster its lithium portfolio further. The combination of promising drill results, strategic project positioning, and supportive regulatory environment positions IRIS Metals as a notable player in the emerging U.S. lithium sector.