Locksley Resources has announced assay results from its initial diamond drilling programme at the El Campo prospect within the Mojave Project in California, US.

The results show the presence of high-grade neodymium and praseodymium (NdPr)-enriched light rare earth element mineralisation.

El Campo is located around 5.5km south-east of MP Materials’ Mountain Pass Mine, currently the only operational rare earth mine in the US, said Locksley.

Assays from the diamond drill-holes at El Campo showed significant total rare earth oxide (TREO) intercepts.

Drill-hole ECDD0002 yielded a peak value of 6.03% TREO over 0.7m, alongside another intersection of 7.20m at 2.93% TREO, which included 3.75m at 4.45% TREO.

Drill-hole ECDD0004 returned 0.90m at 1.09% TREO.

According to the company, neodymium and praseodymium magnet rare earth oxides account for around 25% of the TREO in key intercepts, elements considered critical for permanent magnets and various advanced technologies.

Drilling confirmed that rare earth mineralisation continues below the surface and remains open both at depth and along strike within the wider El Campo corridor.

The results support interpretations that a larger carbonatite system may exist at depth, similar to the Mountain Pass-style mineralisation.

In addition to El Campo, the company reported assay results from its maiden drilling programme at the Desert Antimony Mine.

The final two of eight drill-holes intersected antimony mineralisation beyond historical underground workings.

Peak values included 6.44% antimony over 0.3m and 0.3m at 2.90% antimony in drill-hole DADD0007.

Locksley noted that these results demonstrate continuity of stibnite mineralisation to the south of previous workings.

Following the completion of drilling programmes, exploration at the Mojave Project has progressed to regional targeting and assessment.

Activities include further evaluation of recently acquired radiometric data and plans for a high-resolution ground scintillometer survey at El Campo to guide future exploration.

Locksley Resources non-executive technical director Ian Stockton said: “Diamond drilling at the El Campo prospect represents the first test of the depth extensions of known REE [rare earth element] mineralisation exposed at surface.

“The results are encouraging and consistent with the observations from surface mapping and sampling. We are now evaluating the REE opportunity in the context of our evolving understanding of the Mountain Pass-style magmatic system at El Campo.

“Further work will focus on refining the extent and lithostructural controls on the REE mineralisation and integrating the results into ongoing drill targeting plans, supported by a high-resolution ground scintillometer survey across the entire permit footprint.”

Last month, Locksley signed a binding option agreement with Balmain Minerals, a subsidiary of Sky Metals, to acquire a complete stake in the Iron Duke Copper and Gold Project in New South Wales, Australia.