Southern Hemisphere Mining has pushed visible copper sulphide mineralisation deeper at its Llahuin project in Chile, with diamond drilling confirming continuity down to 256 metres. Assay results are pending, setting the stage for a clearer picture of the system’s scale and grade.
- Visible copper sulphides intersected down to 256m
- Diamond drilling extends mineralisation beneath earlier RC hole
- Supports interpretation of a large porphyry copper system
- JORC-compliant resource estimates reaffirm project scale
- Assay results expected within 4-6 weeks
Diamond Drilling Confirms Depth Extension at Llahuin
Southern Hemisphere Mining (ASX:SUH) has revealed that its latest diamond drilling at the Llahuin Copper-Gold-Molybdenum Project in Chile has intersected significant visible copper sulphide mineralisation extending down to 256 metres. This new depth surpasses the previously reported reverse circulation (RC) drillhole 24LHRC055, which returned 81 metres at 0.53% copper equivalent starting just 2 metres from surface.
The diamond tail extension, drillhole 24LHRD055, was designed to test continuity below the RC hole. Visual logging has confirmed chalcopyrite-bearing veining and disseminated copper sulphides over broad intervals from 84 metres down to 256 metres, suggesting a vertically extensive porphyry copper system. Visible sulphide mineralisation was observed in multiple intervals, with visual estimates ranging from 0.1% to 0.3% sulphide content.
Geological Implications and Exploration Target
Executive Chairman Mark Stowell described the results as "highly encouraging," highlighting that the mineralisation remains open at depth. The findings support Southern Hemisphere’s interpretation of the Cerro-Ferro trend as hosting a substantial porphyry copper system with significant expansion potential. This aligns with the company’s previously reported exploration target of 260 to 340 million tonnes.
While visual estimates provide valuable geological context, the company cautions that these are not substitutes for laboratory assays, which are underway. Core cutting and assay sampling are in progress, with results expected in 4 to 6 weeks. These assays will be critical to determining the grade and economic significance of the intersections and will guide targeting of higher-grade zones within the expanding mineralised corridor.
JORC Resource Estimates and Project Scale
Southern Hemisphere reiterated its JORC (2012) compliant resource estimates for Llahuin, which total approximately 218 million tonnes at 0.38% copper equivalent across measured, indicated, and inferred categories. The resource is distributed across the Central Porphyry, Cerro, and Ferro zones. These estimates are based on metal prices of US$3.50 per pound of copper, US$3,000 per ounce of gold, and US$20 per pound of molybdenum, with no metallurgical recoveries applied yet.
In addition to Llahuin, the company also maintains a substantial manganese resource at its Los Pumas project, with over 30 million tonnes at around 6.2% manganese. Southern Hemisphere confirmed no material changes to the assumptions or technical parameters underpinning these resource estimates.
Ongoing Exploration and Technical Work
Beyond drilling, Southern Hemisphere is advancing geophysical and geochemical studies, including drone magnetics, audio-frequency magnetotelluric surveys, and proprietary 3D porphyry footprint modelling by Fathom Geophysics. These efforts aim to refine geological models and identify promising targets for further drilling.
The company’s recent drilling campaigns have employed industry-standard sampling, logging, and assay techniques, with rigorous quality control and independent verification. Core recoveries average around 95%, and sample preparation is conducted at ALS laboratories in Chile and Peru.
Further updates will follow as assay results are received and interpreted, potentially unlocking new insights into the scale and grade distribution of the Llahuin system.
Bottom Line?
Assay results due in coming weeks will be pivotal in confirming the economic potential of the deeper copper mineralisation at Llahuin.
Questions in the middle?
- Will assays validate the visual estimates and extend the resource base materially?
- How might the expanding mineralised corridor influence Southern Hemisphere’s development strategy?
- What new targets could emerge from ongoing geophysical and geochemical modelling?