Locksley Resources has produced 99.5% pure antimony trioxide from its Desert Antimony Mine feedstock, marking a key step toward restoring a fully domestic U.S. supply chain for this critical mineral.
- 99.5% purity antimony trioxide produced from Mojave Project feedstock
- Supports U.S. government priority to rebuild domestic critical mineral processing
- Metallurgical optimisation program runs alongside DeepSolv™ technology development
- Targets strategic qualification with defense and industrial supply chain partners
- Establishes dual refining pathways to de-risk commercialisation
A Milestone for U.S. Critical Minerals Independence
Locksley Resources Limited (ASX:LKY) has announced a significant metallurgical achievement by producing antimony trioxide at 99.5% purity from feedstock sourced at its Desert Antimony Mine, part of the Mojave Project in California. This breakthrough validates the company’s integrated mine-to-market strategy aimed at re-establishing a 100% American-made supply chain for antimony, a mineral deemed critical for national defense and industrial applications.
Antimony trioxide is a vital component in defense technologies such as munitions primers, military electronics, and flame-retardant systems. The U.S. currently imports the majority of its antimony products, with limited domestic refining capability. Locksley’s success in producing high-purity material domestically addresses this strategic vulnerability, aligning with U.S. government initiatives to restore secure critical mineral processing within allied nations.
Dual Processing Pathways and Strategic Positioning
The metallurgical optimisation program, initiated in late 2025, explores pyrometallurgical processing routes to upgrade Mojave Project mineralisation into refined antimony products. This program runs in parallel with the company’s proprietary DeepSolv™ solvometallurgical technology, creating two independent pathways to reduce development risk and accelerate commercialisation.
Through iterative testing of temperature regimes and chemical processes, Locksley has refined impurity removal techniques to achieve the 99.5% purity threshold, confirmed by X-ray diffraction analysis. While preliminary, this result demonstrates the technical feasibility of producing premium-grade antimony trioxide suitable for strategic defense and industrial markets.
Next Steps Toward Commercialisation
Locksley plans to validate these findings with further ICP metallurgical testing to confirm impurity levels and scale up batch sizes to assess process stability and reproducibility. The company will also evaluate engineering and economic parameters for pilot and commercial refining, including potential toll processing arrangements.
Engagement with strategic partners, metals traders, and government supply chain participants is underway to qualify the high-purity product for specialized markets. This integrated approach positions Locksley as one of the few U.S.-based projects capable of controlling the entire value chain from mining through to refined product specification.
Implications for the U.S. and Allied Supply Chains
With global antimony supply heavily concentrated in China, Locksley’s progress is a timely development amid rising geopolitical and supply chain concerns. The company’s ability to produce high-purity antimony domestically could reduce reliance on foreign sources and support Western defense and industrial sectors that depend on secure access to critical minerals.
Managing Director Kerrie Matthews emphasised the strategic importance of this milestone, highlighting the company’s role in advancing U.S. critical minerals independence through innovative processing and downstream refining capabilities.
Bottom Line?
Locksley’s metallurgical breakthrough sets the stage for a revitalised U.S. antimony supply chain, but commercial scale-up and product qualification remain critical next hurdles.
Questions in the middle?
- How soon can Locksley scale production to commercial volumes with consistent purity?
- What are the timelines and prospects for securing strategic offtake agreements?
- How will U.S. government policies and funding support Locksley’s mine-to-market ambitions?