Resolution Minerals Produces High-Purity Antimony Trioxide from Idaho Project
Jane Morgan Management
Resolution Minerals Ltd (ASX: RML; OTCQB: RLMLF) has successfully produced high-purity antimony trioxide from its Antimony Ridge project in Idaho, marking a key milestone in advancing domestic U.S. supply of the critical mineral and strengthening its downstream processing strategy.
The Company reported that metallurgical test work has generated an intermediate antimony trioxide (Sb₂O₃) product with a purity of 99.38 wt%, produced from large samples of stibnite sourced from historical open pits at Antimony Ridge using conventional pyrometallurgical processing methods.
The results represent an important step in validating potential processing pathways for the project, with further refining test work already underway and final product results expected in the coming weeks.
Metallurgical programs are progressing across multiple streams, including conventional pyrometallurgy, hydrometallurgy and concentrate development. Initial pyrometallurgical test work has been conducted by Kingston Process Metallurgy (KPM) in Canada, while hydrometallurgical studies are ongoing at ANSTO and concentrate optimisation work is being undertaken at IMO laboratories in Australia.
The Company is also advancing plans to establish a hydrometallurgical processing hub in Idaho, aimed at addressing the current lack of modern antimony processing capacity in the United States and enabling a vertically integrated domestic supply chain.
High-grade mineralisation continues to support the project’s development potential, with antimony-bearing stibnite veins consistently returning grades above 30% and up to 50% Sb in recent results. Historical mining at Antimony Ridge supplied material to the U.S. government during World War I, World War II and the Korean War, underscoring the project’s strategic importance.
Adam Roper, PhD, Resolution’s In-house Senior Metallurgist, stated:
“The initial pyrometallurgical results from processing Antimony Ridge samples are very encouraging with few impurities. This is a great start and I’m looking forward to discussing the final results in the coming weeks.
“Resolution’s goal is to develop a processing hub in Idaho for stibnite and I’m relishing the opportunity to bring this to fruition, from mine to product.
“The Johnson Creek Mill site, at the base of Antimony Ridge, is being considered as a fast track option for potential development of a local processing site, given it has the necessary infrastructure on site, with power and water, and is on 10 acres of private land owned 100% by RML.”
Ari Zaetz, RML’s Managing Director, stated:
“With the recent US Government Permitting Council provided via FAST-41 Coverage to accelerate permits, Resolution is in parallel developing further local processing plans to enable antimony and tungsten supply for US demand. Our unique combination of critical minerals assets makes us well placed to deliver.”
Recent 3D modelling of the Antimony Ridge system has highlighted significant scale potential, with multiple antimony and silver-bearing vein swarms extending across an area of approximately 1,000 metres by 700 metres. The project remains open-ended, with expanding exploration upside.
Antimony Ridge forms part of Resolution’s broader Horse Heaven Antimony-Tungsten-Gold-Silver Project in Idaho, which has been selected for U.S. FAST-41 Transparency Coverage. This designation is expected to accelerate permitting timelines for planned large-scale bulk sampling and a drilling program of up to 250 holes.
Looking ahead, Resolution plans to commence bulk sampling of high-grade antimony ore and advance a major drilling program, alongside a Phase 2 campaign at the Golden Gate project targeting gold and tungsten mineralisation. These programs are designed to support resource definition and progress toward a maiden Mineral Resource Estimate.
Antimony Ridge is expected to play a central role in Resolution’s strategy to supply critical minerals, including antimony, tungsten and gold, from Idaho into the U.S. market, supporting growing demand across defence, energy and industrial sectors.
About us:
Resolution Minerals Ltd (ASX:RML) is a mineral exploration company engaged in the acquisition, exploration and development of precious and battery metals - such as gold, copper, cobalt, and uranium.
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Jane Morgan
Jane Morgan Management