Diablo Resources (ASX: DBO) has identified a significant silver-antimony mineral system stretching more than a kilometre across the Utah desert, in results that could reshape the company's near-term drilling strategy.
Diablo announced Monday that first-pass soil sampling at its South Star prospect within the Star Range project has delineated a continuous silver-antimony anomaly exceeding 1,000 metres in length — and geologists say it remains open to the northeast, meaning the deposit could be substantially larger.
The find comes as Washington intensifies its push to secure domestic supplies of critical minerals, with antimony — used in flame retardants, military munitions, and battery technology — now classified as a strategic commodity by the US government.
Rock samples flash high-grade potential
Surface rock sampling is backing up the soil results. Diablo's own field teams have pulled samples returning up to 1,609 grams per tonne silver alongside 4.82 g/t gold from the prospect area. Historical samples from the same corridor previously recorded an extraordinary 8,760 g/t silver — a figure the company is now working to put in context through systematic modern exploration.
CEO Lyle Thorne says the convergence of soil anomalies, old mine workings, and high-grade surface samples points to a system of multiple mineralised veins cutting through the range. "The coming months promise to be both busy and exciting," he said.
Drilling clock is ticking
The company isn't waiting around. A ground-based geophysics survey at the adjacent North Star prospect has already wrapped up, with results being processed to sharpen drill targets ahead of a maiden drilling program pencilled in for the second quarter of 2026.
The Star Range sits roughly six kilometres west of Milford in Beaver County, southwestern Utah — a historically productive mining corridor that once hosted the prolific Horn Silver Mine, which produced 17 million ounces of silver from a single small claim before closing in 1952. Active copper mining continues nearby today.
What comes next
Diablo says it plans to extend soil sampling further to the northeast to chase the open end of the anomaly, while also evaluating whether induced polarisation (IP) geophysics could help image mineralisation at depth across the South Star corridor.
Sixty-two soil samples collected on a 300 metres by 100 metres grid were processed through ALS Global laboratories in Nevada and Vancouver, with assays conducted via four-acid ICP-MS — a standard industry method for this type of system.
The company holds 238 unpatented mining claims covering approximately 18.5 square kilometres, 100% owned, with no known impediments to further exploration or eventual development.