Southern Hemisphere Mining (ASX: SUH) has extended its deepest-ever drill hole at the Llahuin Copper-Gold-Molybdenum Project in Chile to 640 metres, with the company expecting first assay results by late November 2026 as it hunts for a high-grade porphyry feeder zone beneath the Cerro deposit.

The hole, DDLLA028, is a re-entry and extension of a historical diamond hole that originally terminated at 401 metres. Drilling is running 24/7 and is planned to reach approximately 750 metres, targeting a potential feeder zone below the existing mineralisation at Cerro.

The targeting is informed by copper isotope analysis from consultant VectOres, which the company says is helping to vector toward the porphyry source.

While the deep hole progresses, Southern Hemisphere has elevated a newly identified gold-copper prospect to the next slot in its drilling schedule. The target is linked to historical reverse circulation hole RCLLA009, which returned 8 metres at 3.67 g/t gold from 45 metres but was never assayed for copper or other elements.

Recent heavy rainfall eroded riverbanks back to bedrock in the same area, exposing outcrop containing visible chalcocite — a copper sulphide mineral that contains around 80% copper by weight, more than double that of chalcopyrite. Pulps from the historic RC drilling have been dispatched to a laboratory for full multi-element analysis.

The current campaign is an initial approximately 2,000-metre diamond program designed to extend the existing Mineral Resource Estimate at the Cerro Ferro and Ferro South zones. Holes are planned from around 250 metres to a maximum depth of 650 to 750 metres, with scope to extend the program depending on results.

The Llahuin project currently hosts a JORC-compliant Mineral Resource of 218.2 million tonnes grading 0.38% copper equivalent, containing 496,600 tonnes of copper, 654,900 ounces of gold and 12,500 tonnes of molybdenum. Previous drilling has already demonstrated the system’s capacity to deliver higher-grade zones at depth, including 241 metres at 0.42% CuEq from 18 metres (including 143 metres at 0.51% CuEq) and 154 metres at 0.66% CuEq from surface.

Llahuin sits at a relatively low elevation of 1,300 metres in a tier-one mining jurisdiction, approximately 5 kilometres from grid power and 200 kilometres from a major port.

“We’re encouraged with progress on this deep hole extension of DDLLA028 testing for a feeder zone, at 640m now and drilling is continuing,” said Chairman Mark Stowell. “Drilling running 24/7 and first assays due late November 2026, we expect to add more to Llahuin’s potential before year end”.

Stowell added that the new copper-gold prospect provides “further scope to Llahuin’s potential endowment”.

Core samples are being cut and dispatched to laboratories in batches, with initial results expected toward the end of November 2026 based on standard turnaround times. Additional results will be released as they become available. The market will be watching whether the deep hole confirms the presence of a feeder zone — which could materially enhance the project’s grade profile — and whether the new gold-copper target adds a second pillar to the Llahuin story.