Southern Hemisphere Expands Diamond Drilling at Llahuin to Unlock High-Grade Copper Zones

Expanded Drilling Targets Resource Growth

Southern Hemisphere Mining (ASX:SUH) has kicked off an expanded diamond drilling program at its wholly owned Llahuin Copper Project in central Chile, aiming to deepen and widen the footprint of its 3km strike copper-gold-molybdenum porphyry system. The campaign will deliver around 1,000 metres of diamond drilling focused on three key prospects: Ferro South, Ferro Central, and Cerro, targeting both lateral and vertical extensions of mineralisation previously encountered by reverse circulation (RC) drilling halted due to groundwater challenges.

Visible oxide copper exposed during drill pad clearing at Ferro South hints at promising near-surface mineralisation, bolstering confidence in the potential to expand the known resource. The program’s emphasis on testing beneath shallow oxide zones and evaluating primary sulphide targets with higher-grade copper-gold mineralisation aims to unlock further value within the project’s substantial resource base.

Significant Resource Base and Geological Setting

Llahuin hosts a JORC-compliant resource of 218 million tonnes at an average copper equivalent (CuEq) grade of 0.38%, spread across Central Porphyry, Cerro, and Ferro zones. This includes 174 million tonnes in measured and indicated categories, underscoring the project’s scale. The copper equivalent calculation incorporates metal prices of US$3.50/lb Cu, US$3,000/oz Au, and US$20/lb Mo, with preliminary metallurgical testwork indicating recoveries of 84–91% for copper.

The deposit sits within a prolific porphyry belt in central Chile, characterised by classic potassic, phyllic, and argillic alteration zones. Surface oxide copper minerals such as malachite and chrysocolla extend across multiple targets, while anomalous molybdenum and favourable alteration signatures point to significant exploration upside beneath the oxide blanket.

Drill Targets and Methodology

The drilling program builds on previous RC holes that ended in mineralisation, including hole RDLLA134 which intersected 24 metres at 0.78% CuEq from 180 metres depth. Other key holes such as 24LHRD064 and 24LHRD065 showed broad mineralised intervals with grades up to 1.0% CuEq over 26 metres. The diamond drilling will extend these holes to confirm continuity and test for higher-grade sulphide zones.

Sampling and assay protocols remain rigorous, with recent drilling employing industry-standard four-acid digest and fire assay techniques at ALS laboratories in Santiago. Quality control measures include CRM standards and blanks inserted at a rate of 1:20, with independent audits confirming the integrity of sampling and assay data. Core recoveries average around 99%, and drilling is oriented perpendicular to mineralisation to minimise sampling bias.

These efforts follow earlier phases that confirmed a large hydrothermal system at Llahuin, with recent integration of geophysical and geochemical data refining target zones. The expanded drilling complements the company’s broader exploration strategy, which includes ongoing work at the Southern Porphyry target and the Los Pumas Manganese Project in Chile. The company’s recent Phase I drilling confirms extensive porphyry system results provide a foundation for this intensified drilling push.

Upcoming Assay Results and Exploration Outlook

Drilling is underway with first assay results anticipated within weeks. These results will be pivotal in assessing the continuity and grade of extensions to the known mineralisation and may influence future resource updates. The company is also leveraging advanced geochemical footprint modelling and geophysical surveys, including recent magneto-telluric data, to guide exploration.

Southern Hemisphere’s disciplined approach to sampling and data verification, supported by independent competent persons, lends credibility to the exploration program. The project’s location in Chile, the world’s leading copper producer, adds strategic significance amid global demand for copper and battery metals.

As the market digests these developments, attention will focus on assay outcomes and whether the expanded drilling confirms the presence of higher-grade zones that could enhance project economics. The company’s ongoing integration of geological, geochemical, and geophysical data also sets the stage for targeted follow-up drilling campaigns to further delineate the resource.

This drilling campaign at Llahuin is a critical step in Southern Hemisphere’s quest to unlock the full potential of a large-scale porphyry system with multi-element mineralisation, building on its recent broad gold-copper-molybdenum mineralisation confirmation and positioning the company for future growth.