Locksley Confirms High-Grade Rare Earths at El Campo and Extends Antimony at Desert Mine

El Campo Drilling Validates High-Grade NdPr-Enriched Rare Earths

Locksley Resources Limited (ASX:LKY) has delivered encouraging results from its maiden diamond drilling at the El Campo prospect within its Mojave Project in California. The drilling confirms high-grade light rare earth element (LREE) mineralisation enriched in neodymium and praseodymium (NdPr), critical components for permanent magnets and advanced technologies. Notably, the intercepts resemble the Mountain Pass-style carbonatite system, the only operating rare earth mine in the United States, located just 5.5km northwest.

Two of four drill holes intersected significant mineralisation, highlighted by drill hole ECDD0002 returning 7.2 metres grading 2.93% total rare earth oxides (TREO), including a high-grade internal interval of 3.75 metres at 4.45% TREO and a peak 0.7 metres at 6.03% TREO. NdPr accounted for approximately 25% of TREO in key intercepts, underscoring the strategic importance of these elements for sectors such as electric vehicles, defence, and robotics. The drilling also confirmed the mineralised corridor extends along strike for about 1.1km and remains open at depth, suggesting the current program has only tested the upper portion of a potentially larger carbonatite system beneath the surface.

Desert Antimony Mine Drilling Extends High-Grade Stibnite Mineralisation

At the Desert Antimony Mine (DAM), Locksley’s final two drill holes in an eight-hole program have confirmed continuity of high-grade antimony mineralisation beneath historical underground workings. Hole DADD0007 intersected 0.3 metres grading 6.44% antimony (Sb), alongside additional intercepts including 0.3 metres at 2.90% Sb. These results reinforce previous findings that the mineralisation extends southward and remains open along strike and at depth. The antimony occurs in subvertical quartz-stibnite veins within granite gneiss and tonalite, and the company believes the mineralised veins are part of a broader hydrothermal system rather than isolated occurrences.

Geological Insights and Exploration Implications

Locksley’s technical director Ian Stockton highlighted that the drilling has improved understanding of the geological and structural framework controlling mineralisation at both prospects. At El Campo, the mineralisation is hosted within ultrapotassic alkaline intrusive rocks, including shonkinite and syenite, that share geochemical signatures with the Mountain Pass intrusive suite. The presence of thorium-enriched radiometric anomalies aligns with the mapped carbonatite-related rocks, supporting the interpretation of a Mountain Pass-style magmatic system with substantial mantle LREE enrichment.

The company plans to integrate these drilling results into updated 3D geological models to refine future drill targeting. A high-resolution ground scintillometer survey is scheduled at El Campo to better delineate radiometric anomalies and guide step-out drilling. Similarly, at DAM, ongoing structural interpretation aims to define the controls on antimony mineralisation and assess the potential for parallel mineralised structures.

Regional Exploration and Next Steps

Beyond the immediate drill areas, Locksley is advancing regional exploration across the Mojave Project. Enhanced reimaging of thorium radiometric data has identified several high-priority anomalies, now subject to ground scintillometer surveys, geological mapping, and rock chip sampling. The company is also re-assaying historical stream sediment samples for a broader element suite to aid targeting, including for antimony.

Metallurgical and mineralogical assessments of representative mineralised material are underway to support resource evaluation and potential development. The integration of geophysical datasets such as magnetics and gravity will further assist in exploration targeting. These activities align with Locksley’s broader strategy to develop secure domestic supply chains for critical minerals in the US, particularly rare earths and antimony, which are vital for emerging technologies and national security.