Southern Hemisphere Mining Ltd
Drilling Confirms Broad Porphyry Footprint at Llahuin — The Hunt for the High-Grade Core Is On
FMR Resources (ASX: FMR) and joint venture partner Southern Hemisphere Mining (ASX: SUH) have received the final assay results from drillhole 26LHDD073 at Target L within the Southern Porphyry target area of the Llahuin Project in Chile. The results confirm broad copper-gold-molybdenum mineralisation associated with porphyry intrusive phases and stockwork breccias — and critically, the geochemistry supports the interpretation that drilling to date has been cutting through the margins of a larger system, not its core.
That distinction matters enormously for what comes next.
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What the Assays Are Telling the Geologists
Drillhole 26LHDD073 was drilled to a depth of 1,068 metres at the Southern Porphyry target within the Llahuin Project Joint Venture in central Chile. The hole was designed specifically to test structural and geochemical vectors identified from three previous drillholes — 25LHDD070, 25LHDD071, and 26LHDD072.
Southern Hemisphere Mining Llahuin drilling confirms broad porphyry footprint in Chile across multiple target zones within this extensive mineralised corridor. The key assay intervals from 26LHDD073 demonstrate the systematic nature of the exploration programme:
| From (m) | To (m) | Width (m) | CuEq (%) | Zone Description |
|---|---|---|---|---|
| 156 | 180 | 24 | 0.14% | Breccia and Hornfels Zone |
| 582 | 586 | 4 | 0.78% | Porphyry Zone |
The 4-metre interval at 0.78% CuEq from 582 metres depth is particularly notable. It is associated with a mineralised porphyry intrusive phase and sits within the broader context of a hole that encountered multiple porphyry intrusive phases, broad zones of stockwork veining, and pervasive hydrothermal alteration throughout.
Visible chalcopyrite and molybdenite were previously identified in quartz-sulphide, magnetite-sulphide, and anhydrite veinlets across the drillhole, as reported in the 30 March 2026 announcement. Furthermore, the assay results now confirm what the logged geology was suggesting.
Understanding the Full Drilling Picture at Southern Porphyry
Target L results do not sit in isolation — they are the latest piece in a growing body of evidence from Phase I drilling across multiple targets. The table below summarises the significant intersections from all four drillholes completed at the Southern Porphyry to date:
| Drillhole | From (m) | To (m) | Width (m) | CuEq (%) | Zone |
|---|---|---|---|---|---|
| 25LHDD070 | 166 | 167 | 1 | 0.40% | Epithermal Zone |
| 25LHDD070 | 171 | 181 | 10 | 0.45% | Epithermal Zone |
| 25LHDD071 | 258 | 382 | 124 | 0.31% | Polymictic Breccia Zone |
| 25LHDD071 (incl.) | 258 | 278 | 20 | 0.48% | Polymictic Breccia Zone |
| 25LHDD072 | 522 | 626 | 104 | 0.16% | Porphyry and Breccia Zone |
| 25LHDD072 | 814 | 828 | 14 | 0.31% | Breccia and Hornfels Zone |
| 25LHDD072 | 944 | 958 | 14 | 0.21% | Porphyry Zone |
| 26LHDD073 | 156 | 180 | 24 | 0.14% | Breccia and Hornfels Zone |
| 26LHDD073 | 582 | 586 | 4 | 0.78% | Porphyry Zone |
The breadth of mineralisation intersected across these four holes — spanning different depths, lithologies, and target zones — reinforces that the Southern Porphyry is not a narrow, isolated anomaly. It represents an extensive, mineralised corridor where Southern Hemisphere Mining Llahuin drilling confirms broad porphyry footprint in Chile across a six-kilometre strike length.
The Significance of Being on the Margins
"The assays from Target L validate the geological observations from drilling, confirming a broad mineralised porphyry system containing copper, molybdenum, and gold anomalism associated with intrusive phases and stockwork breccia. Importantly, the geochemistry supports our interpretation that drilling to date has intersected the margins of an extensive porphyry system rather than the higher-grade core."
— Oliver Kiddie, Managing Director, FMR Resources
This statement is the crux of the investment narrative here. In porphyry copper systems, mineralisation follows a predictable zonal pattern from the outer edges of a hydrothermal system toward an inner, higher-temperature core where copper and molybdenum grades are typically richest.
The fact that the current drilling has confirmed an extensive mineralised footprint — characterised by stockwork breccias, potassic alteration, and increasing vein complexity at deeper and more proximal targets — without yet hitting the central core is, to experienced porphyry explorers, a very constructive outcome.
Structural measurements from Target L show increasing vein complexity relative to earlier drilling. This is interpreted as a proximity indicator — the geology is telling the team they are getting closer to the fluid source. Multi-element geochemistry and whole-rock analysis are now being used to vector precisely toward that higher-temperature copper-molybdenum core.
What Is a Porphyry Copper System? A Beginner's Guide
For investors less familiar with the geology, understanding what a porphyry copper system is — and why the zonal structure matters — is key to appreciating the significance of these results.
What Is a Porphyry Copper Deposit?
A porphyry copper deposit is one of the world's most economically important types of mineral deposit. They are large-tonnage, typically low-to-moderate grade accumulations of copper — often with gold and molybdenum — formed by hot, metal-bearing fluids that rise from a cooling magmatic intrusion and flow outward through fractures and breccias in the surrounding rock.
Over time, these fluids cool and deposit their metals as sulphide minerals — primarily chalcopyrite for copper and molybdenite for molybdenum.
Why Does the Zonal Model Matter?
Porphyry systems are characterised by concentric alteration and mineralisation zones radiating outward from the fluid source. The innermost zones are typically the highest grade and are associated with potassic alteration and abundant sulphide veining.
Moving outward, grades decrease and alteration styles change. The epithermal veins and breccias encountered in earlier drilling are characteristic of the outer, upper portions of the system. The deeper intersections, with increasing vein complexity and potassic signatures, suggest proximity to the core.
Why Does This Matter for Investors?
The current drilling has systematically mapped the outer architecture of what appears to be an extensive porphyry system. The team now has a set of vectors — structural, geochemical, and geophysical — pointing toward where the grades should be strongest. Phase II drilling, planned for Q4 2026, will test that interpretation directly.
Glossary of Key Terms
- CuEq (Copper Equivalent): A single figure that combines the value of copper, gold, and molybdenum into a copper-normalised grade for comparison purposes. Calculated using assumed metal prices and recovery factors.
- Stockwork breccia: A rock broken into angular fragments by hydrothermal fluids and infilled with veins of sulphide minerals — a classic hallmark of porphyry systems.
- Chalcopyrite: The primary copper sulphide mineral in most porphyry deposits, appearing as a brassy yellow mineral in core.
- Molybdenite: A molybdenum sulphide mineral, often appearing as silvery flakes, frequently associated with the higher-temperature core of porphyry systems.
- Potassic alteration: A high-temperature alteration assemblage typically found closest to the porphyry fluid source, often correlating with the highest-grade mineralisation.
- IP / MT (Induced Polarisation / Magnetotellurics): Geophysical survey methods used to detect subsurface features — in this context, the sulphide bodies and structural conduits associated with porphyry mineralisation.
The Llahuin Project in Context: A Substantial Resource Already in Hand
The Southern Porphyry exploration is occurring within the broader Llahuin Project, which already hosts a substantial JORC-compliant resource across its established zones. That existing resource base provides important context for the scale of what the project could ultimately represent.
Llahuin Copper-Gold-Molybdenum Project — JORC (2012) Resource Summary
(as announced 30 July 2025)
| Zone | Measured (Mt @ CuEq%) | Indicated (Mt @ CuEq%) | Total M+I (Mt @ CuEq%) | Inferred (Mt @ CuEq%) |
|---|---|---|---|---|
| Central Porphyry | 90.9 @ 0.42% | 10.2 @ 0.33% | 101.1 @ 0.41% | 24.5 @ 0.31% |
| Cerro | 41.9 @ 0.40% | 4.9 @ 0.32% | 46.8 @ 0.39% | 13.7 @ 0.32% |
| Ferro | 19.1 @ 0.32% | 7.1 @ 0.34% | 26.2 @ 0.32% | 5.9 @ 0.32% |
| Total | 151.9 @ 0.40% | 22.2 @ 0.33% | 174.1 @ 0.39% | 44.1 @ 0.31% |
Total Measured, Indicated and Inferred: 218.2 Mt @ 0.38% CuEq
Resources are reported above a 0.22% CuEq cut-off grade. Preliminary metallurgical recoveries from closed circuit flotation testwork confirmed copper recoveries of 84–91%, gold recoveries of 41–57%, and no deleterious elements in the flotation concentrate.
The Southern Porphyry target sits within this extensive project area — a six-kilometre-long mineralised corridor that hosts multiple copper-gold-molybdenum porphyry centres and remains substantially underexplored relative to the established resource zones.
The Work Underway to Find the Core
The team is not simply waiting for Phase II drilling. In addition, a rigorous, multi-dataset integration programme is actively underway to maximise the precision of the next drill targets:
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Thin-section petrography of key lithologies and alteration assemblages is ongoing to characterise mineral relationships, alteration zoning, and paragenesis — reconstructing the geometry of the porphyry system in three dimensions.
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Multi-element geochemical analysis is being used to identify alteration patterns and elemental associations that indicate proximity to the porphyry core. Certain trace elements behave predictably in porphyry systems and function as pathfinders toward higher-grade zones.
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Geophysical and petrophysical integration — downhole datasets from all four drillholes are being interrogated against existing surface IP and MT geophysical models. Selected samples have also been submitted for petrophysical testwork including density, magnetic susceptibility, resistivity, and chargeability measurements.
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Structural dataset integration — structural measurements collected during drilling are being combined with the above datasets to build a three-dimensional model of the porphyry system and identify the most likely locations of the mineralised core.
What Comes Next: Milestones to Watch
| Milestone | Status / Timeline |
|---|---|
| Final assay results — 26LHDD073 (Target L) | Received — June 2026 |
| Integration of assays, petrography and multi-element geochemistry | Ongoing |
| Integration of geological and geophysical datasets from Targets A, C, K and L | Ongoing |
| Refinement of 3D porphyry model and vectoring interpretation | Ongoing |
| Finalisation of Phase II drill targets — porphyry core | In progress |
| Phase II drilling — targeting interpreted porphyry core | Planned Q4 2026 |
The Phase II programme will be informed by one of the most comprehensive multi-dataset integration exercises the project has seen, combining four drillholes of geological data with surface geophysics, petrography, and multi-element geochemistry. As a result, the drilling targets will be materially better constrained than those in Phase I.
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Why This Project Deserves Investor Attention
Several elements of the Llahuin story combine to make this an investment situation worth tracking carefully.
Scale and Exploration Logic
Scale of the existing system: A 218.2 Mt total resource at 0.38% CuEq across the established zones is already a meaningful inventory by global porphyry standards. The Southern Porphyry represents a separate, potentially additive mineralised corridor within the same project concessions.
The exploration logic is sound: Phase I drilling has followed a disciplined, target-by-target approach — Targets A, C, K, and now L — systematically building a geological and geophysical picture of the Southern Porphyry. The increasing vein complexity and the geochemical signatures observed at Target L are consistent with the team approaching the porphyry core rather than moving away from it.
Jurisdiction, Metallurgy, and Catalysts
Chile is the world's foremost copper jurisdiction: The Llahuin Project is located in Chile, the world's leading copper-producing country, in a region that has hosted major porphyry copper discoveries. The geological setting is proven and well understood.
Metallurgy supports confidence in recoveries: Preliminary flotation testwork on the existing Llahuin resource has confirmed copper recoveries of 84–91% and no deleterious elements in concentrate — a commercially relevant result that supports the viability of the broader project.
A defined catalyst ahead: Phase II drilling is planned for Q4 2026, targeting the interpreted higher-grade core of the Southern Porphyry. This provides a clear, time-bound catalyst around which the investment thesis can be assessed.
However, the most significant test of the exploration thesis remains ahead. Where Southern Hemisphere Mining Llahuin drilling confirms broad porphyry footprint in Chile, the geological vectors point toward a higher-grade core that could transform the project economics if successfully intersected.
Key Takeaway: FMR Resources and Southern Hemisphere Mining have confirmed a broad, mineralised porphyry system at the Southern Porphyry target within the Llahuin Project — and the geological evidence points toward the highest-grade core remaining untested. With Phase II drilling targeting that core planned for Q4 2026, and a rigorous multi-dataset integration programme actively refining the drill targets, the most important chapter of the Southern Porphyry story is yet to be written. Against the backdrop of an existing 218.2 Mt resource at 0.38% CuEq across the wider Llahuin Project, investors with an interest in large-scale copper-gold-molybdenum discovery in one of the world's premier mining jurisdictions should be watching this closely.
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