OD6 Metals (ASX:OD6) has reported that the historic drilling at the Horseshoe Fluorspar Deposit in Nevada confirms ‘exceptionally high-grade’ mineralisation from surface.
As previously reported, the company acquired a rare dataset of geological records from Union Carbide Corporation in May 2026, including a summary report and assay sheets from the four-hole program.
Four shallow drill holes completed by Union Carbide Corporation in 1958 intersected significant widths of high-grade calcium fluoride (CaF₂) mineralisation at the project.
The drilling targeted the southern corner of the system and did not test the ‘high-grade’ core later exposed in open-pit mining.
Significant intercepts include 14.3m at 70.9% CaF₂ from surface, with a peak result of 84% CaF₂ over 1.5m; and 14m at 59.9% CaF₂ from 19.5m, including a peak result of 86.7% CaF₂ over 1.5m.
Hole H1 returned 25.8m at 46.2% CaF₂ from 0.9m, including 12.8m at 60.9% CaF₂ from 0.9m, with a peak result of 93.7% CaF₂ over 1.2m.
Multiple sections of core were never assayed yet logged with fractured breccia and vein material, which may be fluorspar-bearing. According to the company, this indicates that mineralised widths may be materially greater than historic drilled widths.
Managing Director Brett Hazelden notes that the historic data indicates “a rare combination of exceptional high-grade and significant widths, with results well above typical fluorspar benchmarks”.
“Importantly, these intercepts were returned from the margin of the system, not the high-grade core later exposed in open pit mining and were notably only selectively assayed,” Hazelden says.
“This indicates the system has the potential to be both higher grade and larger than intercepted in historic drilling.”
He adds that the mineralisation remains open in all directions as well as untested at depth.
The US is currently wholly reliant on imports of fluorspar, highlighting the strategic importance of domestic supply. Fluorspar is listed on the US Critical Minerals list, with applications in battery technologies, artificial intelligence chip manufacturing, nuclear fuels, aerospace, and defence technologies.
The company now plans to digitise scanned paper logs and cross-sections into a geological model, expand systematic channel and rock chip sampling, and validate historic ‘high-grade’ results.
Future work includes detailed geological and structural mapping, soil geochemistry programs, and identifying drill targets ahead of permitting for maiden drilling.
OD6 Metals is an Australian exploration and development company focused on critical minerals projects, including rare earths, copper, and fluorspar.
Write to Amy Rotman at Mining.com.au
Images: OD6 Metals
