• IRIS Metals has acquired the 752-hectare Tin Mountain Extension property, increasing the Tin Mountain Project footprint
• This acquisition strengthens IRIS' position as a dominant lithium regional explorer in the U.S. with over 2105 federal claims and patented claim blocks
• Phase II drilling underway at Tin Mountain targeting high-grade lithium zones, with assays expected in October 2025 and a maiden mineral resource estimate on track for late 2025

IRIS Metals Limited (ASX: IR1) has announced the acquisition of the Tin Mountain Extension (TME) property, located adjacent to its Tin Mountain Project in South Dakota, USA. Through its subsidiary Tin Mountain Minerals LLC, IRIS has entered into a binding agreement to purchase 93 federal mining claims covering 752 hectares from Rapid Critical Metals Limited's subsidiary. This acquisition aligns with IRIS' strategy to consolidate high-potential lithium projects in the Black Hills, reinforcing its position as the region's leading lithium explorer. The TME property is on strike with known lithium mineralization at the former Tin Mountain Mine and includes historical mines with geological structures indicative of significant lithium potential. The acquisition includes a share issuance of US$550,000 in IR1 shares, a US$300,000 cash payment, and a 2% gross revenue royalty to the original claim vendor. IRIS has also commenced a Phase II drilling program at the Tin Mountain Project, targeting high-priority zones beneath the historical mining cavern. Assays are expected in early Q4 2025, supporting a maiden mineral resource estimate planned for late 2025. The Black Hills of South Dakota are renowned for their lithium pegmatites, and IRIS controls a significant portfolio of projects in the region, including the Beecher, Edison, and Helen Beryl projects, in addition to Tin Mountain. The company's 'Hub & Spoke' strategy focuses on centralized processing of lithium from multiple projects, reducing costs and accelerating development. With growing demand for lithium and other critical minerals, IRIS is well-positioned to supply U.S.-sourced materials for battery production and renewable energy technologies.

IRIS is moving to quickly grow mineral resources and advance processing studies to support a multi-mine production unit towards economic analysis in early 2026.