Locksley Resources' (ASX:LKY) Major Technical Milestone in U.S.-Based Green Processing for Antimony

Jane Morgan Management

16 October 2025 – Perth, Australia | Locksley Resources Limited (ASX: LKY, OTCQX: LKYRF, FSE: X5L) (“Locksley” or the “Company”) is pleased to announce significant progress for its collaborative R&D program with Rice University in Houston, Texas, which is aimed at advancing a new environmentally sustainable processing technology for antimony.

The project, focused on the development of the proprietary DeepSolv™ Deep Eutectic Solvent (DES) system, has achieved several key preliminary technical milestones. These include the establishment of process parameters for a green hydrometallurgical extraction process that supports scoping of a future pilot demonstration plant. 

Locksley’s Chief Operating Officer, Mr Danny George, recently visited Rice University to review the laboratory-based DES research program that is being led by Professor Pulickel Ajayan of the Rice Advanced Materials Institute. 

The DES system has shown significant potential for selective dissolution of antimony sulphides under mild conditions using environmentally benign ionic mixtures. This offers a promising alternative to traditional, more hazardous reagents, and lays the foundation for a low-emission, scalable antimony production pathway. 

The technical sessions during the visit addressed a range of process optimisation parameters, which included solvent composition, leach kinetics, temperature controls, and reagent recyclability. Importantly, mass-balance modelling was initiated to correlate lab-scale results with commercial-scale processing, with particular attention to solvent recovery and downstream metal recovery efficiency. 

Mr Danny George, Locksley Chief Operating Officer commented; 

“It was a privilege to spend time with the talented team at Rice University and see firsthand the impressive progress being made. The collaboration continues to deliver strong technical outcomes, and we’re excited about how this work is shaping the foundation for future commercial application. 

The novelty of the DES-based process lies specifically in the solvent chemistry and its enhanced selectivity for antimony dissolution—representing a true breakthrough in reagent innovation rather than a complete process redesign. 

Importantly, the downstream processing stages utilise established hydrometallurgical methods, ensuring a clear pathway toward commercial scalability, operational reliability, and regulatory acceptance. This is a strong example of how academic innovation and industry experience can work hand in hand to deliver next-generation solutions for the critical minerals sector.” 

As part of the next phase of development, flotation concentrates and ROM ore samples from Locksley’s Desert Antimony Mine (DAM) and EV Resources’ Los Lirios deposit will be delivered to Rice University. These samples will support an expanded testwork program, which will underpin design and scoping for a pilot demonstration plant. 

Locksley’s efforts to develop an American-made mine-to-metal antimony supply chain align with U.S. national priorities for critical minerals independence and economic security. 

For further information, please contact:

Kerrie Matthews
Chief Executive Officer
Locksley Resources Limited
[email protected]

Jane Morgan
Jane Morgan Management
Investor & Media Relations
[email protected]

ABOUT LOCKSLEY RESOURCES LIMITED

Locksley Resources Limited is focused on critical minerals in the United States of America. The Company is actively advancing the Mojave Project in California, targeting rare earth elements (REEs) and antimony. Locksley is executing a mine-to-market strategy for antimony, aimed at re-establishing domestic supply chains for critical materials, underpinned by strategic downstream technology partnerships with leading U.S. research institutions and industry partners. This integrated approach combines resource development with innovative processing and separation technologies, positioning Locksley to play a key role in advancing U.S. critical minerals independence 

MOJAVE PROJECT

Located in the Mojave Desert, California, the Mojave Project comprises over 491 claims across contiguous prospect areas, namely, the North Block/Northeast Block and the El Campo Prospect. The North Block directly abuts claims held by MP Materials, while El Campo lies along strike of the Mountain Pass Mine and is enveloped by MP Materials’ claims, highlighting the strong geological continuity and exploration potential of the project area. 

In addition to rare earths, the Mojave Project hosts the historic “Desert Antimony Mine”, which last operated in 1937. Despite the United States currently having no domestic antimony production, demand for the metal remains high due to its essential role in defense systems, semiconductors, and metal alloys. With significant surface sample results, the Desert Mine prospect represents one of the highest-grade known antimony occurrences in the U.S. 

Locksley’s North American position is further strengthened by rising geopolitical urgency to diversify supply chains away from China, the global leader in both REE & antimony production. With its maiden drilling program planned, the Mojave Project is uniquely positioned to align with U.S. strategic objectives around critical mineral independence and economic security

Jane Morgan
Jane Morgan Management
Investor & Media Relations
[email protected]