Key Highlights

•  First-pass surface sampling at Cupric, with 27 surface grab and continuous channel samples, confirmed tungsten mineralisation alongside copper and gold in a skarn setting.

•  The Horn project in Beaver County, Utah, covers about 13.2 square kilometres, and Diablo holds an 80 per cent interest.

•  Underground sampling, mapping and surveying of two historical adits is under way, with further mapping and sampling planned.

Diablo Resources Ltd (ASX:DBO) has reported first-pass surface sampling results from the Cupric prospect at its Horn project in Utah, confirming tungsten mineralisation alongside copper and gold in a skarn setting. The exploration update was released on 26 October 2026.

The Horn project lies in Beaver County, south-western Utah, within the historic Frisco mining district about 20 kilometres west of Milford. Diablo now holds an 80% interest after acquiring the consolidated tenure in early September 2026. The project covers about 13.2 square kilometres across 101 patented and 101 unpatented claims.

What the sampling found

According to the release, Diablo collected 27 surface grab and continuous channel samples at Cupric. Six samples returned more than 0.1% tungsten trioxide (WO₃), with the best grab sample, HS26-106, grading 0.37% WO₃. Sample HS26-71 returned 0.22% WO₃, while HS26-107 returned 0.17% WO₃ with 2.82 g/t gold.

Copper and gold grades were also notable. Grab sample HS26-90 returned 12.5% copper, 3.29 g/t gold and 398 g/t silver, and a grab of mine dump material returned 11.9% copper and 2.56 g/t gold. Channel sampling returned 4.5 metres at 1.26% copper and 0.46 g/t gold, and 2.6 metres at 1.56% copper including 1.3 metres at 0.12% WO₃. A third channel returned 3.0 metres at 1.00% copper and 0.11 g/t gold.

Grab samples are selective by nature and can overstate the grade of a broader zone. Channel results give a better sense of continuity at surface, but none of these results indicate grade or width at depth, and no drilling has yet been completed by Diablo at Cupric.

Chief executive Lyle Thorne said the initial sampling had "confirmed tungsten mineralisation" associated with copper and gold.

Geology and history

Diablo describes Cupric as a scheelite-bearing skarn next to a quartz monzonite intrusion. The company has identified three tungsten-bearing zones, labelled Areas A to C, with Area A its main focus. Diablo also said surface rock sampling across multiple structural corridors elsewhere at Horn returned strong silver, gold, copper, zinc and lead grades, although it did not provide figures. Two adits were developed at the prospect in 1942–43 by the US Bureau of Mines with the Desert Silver Mining Company.

The release cites historical production of 17 million ounces of silver at 604 g/t from the wider district. That is historical production, not a mineral resource, and the 1940s data has not been verified under the JORC Code. Diablo has not reported a resource or exploration target at Horn.

Why it matters

Tungsten is widely regarded as a critical mineral and US-based projects have attracted growing attention as Western governments look to diversify sources. Diablo is positioning Horn as a multi-commodity project, with other targets including the Horn Mine, Imperial, Accrington and Washington prospects. Its Star Range silver-antimony project lies about 15 kilometres away.

The combination of tungsten, copper, gold and silver at surface gives the company several possible pathways, but the project remains at an early reconnaissance stage. The release did not disclose funding details, and the cost of an initial drilling programme will be an important consideration for a small explorer.

Next steps

Diablo said underground sampling, mapping and surveying of the two historical adits is underway. The company also plans further mapping and sampling to define anomalies, petrological work and a review of previous exploration for other tungsten zones across the project.

The Cupric results will be integrated into target ranking ahead of a maiden drilling programme scheduled for the first quarter of 2027. Drill results from that programme will be the first test of whether surface tungsten and copper-gold mineralisation extends to depth in meaningful widths and grades. Permitting, access and funding will influence how quickly that work proceeds.