Black Bear Minerals (ASX:BKB) has reported re-analysis of historic drill core indicates ‘higher-grade’ silver and polymetallic mineralisation at its Shafter Silver Project in Texas, US.
The company says the initial historical core re-analysis returned higher contained silver than historical assay results.
Key results include SW5 returning 6.7m @ 408 grams per tonne silver (Ag) from 9.1m, including 1.2m @ 1,222g/t Ag, representing a 54% increase in contained Ag versus the historic intercept of 6.7m @ 266g/t Ag from 9.1m.
Drill hole 201200306 returned 23.8m @ 147g/t Ag from 5.5m, including 10.4m @ 231g/t Ag, compared to the historically reported drill intercept of 23.8m @ 134g/t Ag from 4.9m.
The re-analysis program also identified gold mineralisation in drill cores that had not previously been analysed for gold. The company says the results highlight broader polymetallic potential beyond the silver-only Shafter foreign mineral resource estimate (MRE).
Hole 201200602 returned 3.1m @ 181g/t Ag, 0.70g/t Au, 1.1% lead (Pb) and 3.4% zinc (Zn) from surface, with a peak gold intercept of 1.2m @ 1.50g/t Au from 1.8m. The original result was 3.1m @ 134g/t Ag from surface.
“These are outstanding results, with re-analysis of historic core returning 6.7m at 408g/t silver, a 54% increase in contained silver across the broader interval, and confirming peak grades up to 1,222g/t silver,” CEO Dennis Lindgren says.
“Together with the encouraging twin-hole results, this continues to strengthen our confidence in the quality, continuity, and growth potential of the Shafter mineralised system, while providing a clear basis to expand the historic core re-analysis program in supporting key catalysts including advancing JORC conversion, continuing exploration, and progressing the Shafter restart studies.”
The Shafter Silver Project, located in Presidio County, Texas, sits within a basin carbonate sequence that extends 1,600km from northern Mexico through southwest Texas, lying in an extension of Mexico’s Eastern Sierra Madre Belt, which hosts Peñasquito mine.
The company first announced the foreign estimate for the project in October 2025. The estimate was prepared under Canadian NI 43-101 and is not reported in accordance with the JORC Code (2012).
The mineralised zone at Shafter spans approximately 4km of strike from west to east. The central portion outcrops at the surface at the intersection between the MacDaniel and Mina Grande Faults and was historically worked as the Presidio Mine from 1883 until 1942, producing 35.2 million ounces Ag at an average grade of 521g/t Ag.
The company attributes the increase in reported silver grades to additional wall rock assays and expanded sampling around historic mineralised intervals. It says multi-element and gold analysis has also identified polymetallic mineralisation beyond the historic silver-only foreign estimate.
Black Bear says it will expand re-analysis across additional historic drill programs and extend coverage across the foreign estimate footprint.
Black Bear Minerals says it plans limited infill drilling to support conversion of the foreign estimate to a maiden JORC mineral resource estimate and advance the Rapid Mine Restart Study. The company is also updating its geological models and plans further drilling to test extensions to mineralisation beyond the current foreign estimate.
Write to France Pinzon at Mining.com.au
Images: Black Bear Minerals
