Broad intersections of mineralised stockwork Breccia & Porphyry at Target L within Llahuin Copper Project

⚒️ Southern Hemisphere Mining Limited advises that diamond drillhole 26LHDD073, the fourth hole of the Phase I program at Southern Porphyry, has been completed to a final depth of 1,068.0 metres at Target L, intersecting multiple broad, mineralised stockwork breccia and porphyry intrusive phases.

The Southern Porphyry target is within the Llahuin Copper-Gold-Moly Project Joint Venture with FMR Resources Limited (ASX: FMR), Chile.

• Drillhole 26LHDD073 completed to a depth of 1,068.0m at Target L
• The drillhole intersected multiple broad, mineralised stockwork breccia and porphyry intrusive phases between 144m and 815m depth downhole
• Visible* copper and molybdenite observed within quartz–sulphide veinlets, anhydrite veinlets, and disseminations in and around porphyry intrusions

View the Full PDF of the ASX Announcement

Photo 1. Molybdenite mineralisation in quartz vein 817 m downhole in 26LHDD073* (refer to Appendix 1).

FMR Resources Managing Director, Mr Oliver Kiddie, commented:

“Drilling at Target L has intersected broad zones of variably mineralised stockwork breccia and porphyry. The visible copper and molybdenite sulphide, combined with the alteration and brecciation textures, are interpreted to mark the edge of an elongate mineralised porphyry intrusive corridor, first intersected in Target K. The next critical step in additional drillhole targeting requires full-suite assays, specifically the multi-element geochemistry, to fingerprint alteration signatures to vector to the core of this extensive, mineralised system.”

“Phase I drilling was planned for ~4,000m, designed to test a conceptual porphyry target under volcanic cover. At completion, FMR has drilled +5,000m, intersected a shallow, mineralised epithermal system, and an extensive, mineralised porphyry system below. The Phase II drill program will be designed through integration of geological, geochemical, and geophysical datasets, with a clear aim of targeting the mineralised core of the Southern Porphyry system.”

Target L was defined from alteration, geophysical and vein orientation vectors to the south and east of Target A, C, and K drilling. The 26LHDD073 drill collar is located on the same drill pad as Target C to intersect the broad south and east geological, structural, and geophysical target.

Geological Summary – 26LHDD073

Drillhole 26LHDD073 intersected multiple porphyry-related intrusive phases, including Andesitic Porphyry, Quartz-Diorite and Granodiorite Porphyry. These intrusive units are associated with stockwork veinlets, pervasive silicification, and breccia development which are interpreted to represent porphyry-style hydrothermal fluid phases.

Broad zones of visible sulphide mineralisation* were recorded within several intrusive intervals, including chalcopyrite within quartz–sulphide, calcite-sulphide and magnetite-sulphide veinlets and molybdenite hosted in quartz and anhydrite veins (see Photos 1 and 2, and Appendix 1). Additionally sooty chalcocite was observed in a pyrite vein at 49.7m, indicating development of supergene weathering and enrichment processes at Southern Porphyry.*

Copper anomalism confirmed with pXRF is associated with fractured and brecciated porphyry intrusive phases, confirming the presence of a copper–molybdenum sulphide assemblage typical of mineralised porphyry systems.

Photo 2. Zone of intense pyrite and quartz vein stockwork with fine disseminated pyrite 372m downhole in 26LHDD073* (refer to Appendix 1).

*Cautionary Statement: Visual estimates of mineral abundance should never be considered a proxy or substitute for laboratory analyses where concentrations or grades are the factor of principal economic interest. Visual estimates may also provide no information about impurities or deleterious physical properties relevant to valuations.

The presence of porphyry intrusions, with associated visible copper and molybdenum sulphides, indicates that 26LHDD073 is located within the mineralised intrusive system footprint (see Figure 3).

Downhole geophysical data from Target L is currently being collected and processed before integration with existing geophysical models and downhole data from Targets A, C and K.

Figure 1. Plan view of Southern Porphyry, showing surface projections of geophysical models, mapped epithermal veining at surface, and planned drill targets*. * Refer to FMR ASX announcements dated 9 July 2025, 26 August 2025, 23 October 2025, 10 November 2025, 25 November 2025, 3 December 2025, 3 February 2026, 10 February 2026, 26 February 2026 and 5 March 2026.

Figure 2. Cross section L-L’, Target L – 26LHDD073, showing geophysical models and completed drillhole to 1,068.0m downhole depth, including mid-level shallow IP Resistivity and IP Chargeability features and the large MT high amplitude feature at depth (+/- 10m window)* intersected in 25LHDD071 and interpreted as pyrite rich peripheral mineralisation. The mineralisation photographs are of sooty chalcocite at 49.7m, molybdenite in anhydrite vein 583.1m, molybdenite in quartz vein 654.8m, chalcopyrite in matrix 688.2m, chalcopyrite in quartz 788m, chalcopyrite in magnetite vein 803m, molybdenite in quartz vein 817m, chalcopyrite in sulphide vein 1032.7m and in quartzanhydrite vein at 1034.7m. * Refer to FMR ASX announcements dated 9 July 2025, 26 August 2025, 23 October 2025, 10 November 2025, 25 November 2025, 3 December 2025, 3 February 2026, 10 February 2026, 26 February 2026, and 5 March 2026.

Figure 3. Hydrothermal alteration zones associated with porphyry copper deposits (modified after Lowell & Guilbert 1970) with interpreted locations of completed FMR drillholes 25LHDD070, 25LHDD071, 26LHDD072 and 26LHDD073.

Structural and Geophysical Vectoring

Structural measurements from drillholes 25LHDD070 and 25LHDD071 define a consistent sheeted vein set striking NNE with moderate ESE dip. In contrast, vein orientations in 26LHDD072 are more variable, with an average ENE strike and moderate SSE dip. This change in orientation is interpreted to reflect increasing structural complexity toward a fluid source, providing a vector to the south, east, and at depth relative to Target K.

Structural measurements from 26LHDD073 are variable but can be categorised into a shallow structural set dipping SE which transitions to a deeper NW trend. The transition downhole indicates that the vein sets represent different intrusion related fluid pulses or that drilling may have traversed above and across the fluid source.

Existing drilling is interpreted to have intersected the edges of an elongate mineralised porphyry intrusive corridor. Vectoring towards the porphyry source requires the combination and interpretation of all geophysical, geological and whole rock geochemical data.

Whole-Rock Geochemistry and Petrography

Thin-section petrography of key lithologies and alteration assemblages is ongoing to characterise mineral relationships, alteration zoning and paragenesis, contributing to the reconstruction of porphyry system geometry. Geochemical analysis of anhydrite–pyrite samples continues.

Multi-element geochemical data are being analysed in conjunction with petrographic observations to identify alteration patterns and elemental associations indicative of proximity to the porphyry core. Integration of these datasets will assist in refining geochemical vectors and prioritising subsequent drill targeting within the Southern Porphyry system.

Geological Setting

The Southern Porphyry target is located within a six-kilometre-long mineralised corridor within the Llahuin Project, which hosts multiple copper–gold–molybdenum porphyry centres (see Figure 4). Field mapping completed in June and July 2025 identified argillic alteration, silicification and epithermal quartz veining at the surface, along with zones of secondary copper mineralisation assemblages typical of the upper levels of a copper porphyry system.*

Re-logging of historic drillholes confirmed these features at depth, with intervals showing hydrothermal alteration, silicification, and disseminated chalcopyrite–pyrite mineralisation. These observations suggest a telescoped system, characterised by epithermal-style veining and alteration preserved above a deeper porphyry core.*

*Refer to FMR ASX announcement “Phase I Drilling Target Areas Refined at Southern Porphyry” dated 9 July 2025

FIGURE 4 = Map

Figure 4. Southern Porphyry target area within the Llahuin Project Joint Venture concessions.

Next Steps

• Complete integration of geological and downhole geophysical datasets from Targets A, C, K and L.
• Refine three-dimensional interpretation of the porphyry system.
• Provide updates regarding assay results and interpretations from the Phase I program. Assays results for all holes are expected to be received in the June 2026 quarter.
• Design Phase II drilling program to continue testing the Southern Porphyry target area.

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Southern Hemisphere Mining Limited is an experienced minerals explorer in Chile, South America.

Chile is the world’s leading copper producing country and one of the most prospective regions of the world for major new copper discoveries. The Company’s projects include the flagship Llahuin Porphyry Copper-Gold-Moly Project and the Los Pumas Manganese Project, both of which were discovered by the Company.

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