Rincon Resources Commences RC Drilling at Telfer South Gold-Copper Project
Rincon Resources Limited (ASX: RCR) has announced significant results from a newly completed MobileMT geophysical survey across its 100%-owned Telfer South–Hasties Project in Western Australia's Eastern Pilbara region. The survey, covering approximately 89 line-kilometres of airborne data, has identified a previously unrecognised, high-resistivity body positioned more than 200 metres below surface, located directly along strike of the known Hasties Gold-Copper zone. Significantly, this depth target has never been tested by drilling.
The identification of this deep resistive target, alongside multiple additional zones of interest across the project, materially enhances the exploration outlook at Telfer South and provides a compelling framework for an upcoming RC drilling programme. Details of the Rincon Resources Telfer South depth target drilling plans are expected to be announced in the coming weeks.
The Hasties Gold-Copper zone has served as the focal point of Rincon's exploration activities at Telfer South, hosting a Mineral Resource Estimate (MRE) of 870,000 tonnes at 0.96 g/t Au for 26,800 oz gold and 2,286 tonnes of copper (at a 0.3 g/t Au cut-off). The zone extends over 1.1 kilometres of strike and is located just 10 kilometres south of the Telfer Gold Mine, one of Australia's most significant gold-copper producing operations.
Historical exploration at Hasties has been predominantly confined to near-surface and shallower drilling intervals. The MobileMT survey fundamentally changes this approach by imaging the subsurface geology to depths approaching 1 kilometre, effectively opening an entirely new vertical dimension for the project.
"The MobileMT geophysical survey has added a new dimension to our Hasties Gold-Copper project, located just 10 km south of the Telfer Mine in the East Pilbara, providing timely data for our planned RC drilling program. The targets identified by the survey align well with the Hasties Zone, which now extends for over 1.1 km."
— Michael Griffiths, Technical Director, Rincon Resources
The MobileMT survey, conducted by Expert Geophysics Surveys Inc., has identified four distinct targets across the project. Each target displays different geological characteristics and warrants varying levels of follow-up investigation.
| Target | Location | Key Characteristic | Status |
|---|---|---|---|
| Deep Resistive Body | Along Hasties Zone strike | 200m+ depth, 7,500/1,200 ohm.m readings | Undrilled — priority drill target |
| Hasties Central | Near-surface breach of resistive unit | Coincides with historic rock-chip samples up to 37 g/t Au and 21% Cu | Ground assessment planned |
| Padion Prospect | ~4 km north-west of Hasties zone | Second resistive unit coinciding with surface geochemistry anomalies | Recently discovered, follow-up planned |
| Two Additional Zones | Various locations across project | Smaller resistive anomalies | Ground truthing scheduled |
The resistivity readings from the deep target — 7,500 and 1,200 ohm.m — are particularly noteworthy. These elevated values indicate the presence of resistive rock units that, within the context of the Hasties geological setting, are interpreted as host rocks and possibly concealed intrusive material.
Known mineralisation at Hasties has developed along a pronounced resistivity gradient, providing geological support for the depth target as a potential extension of the mineralised system.
MobileMT (Mobile Magnetotellurics) represents a helicopter-borne, passive-source electromagnetic (EM) geophysical method. Rather than transmitting an active signal into the ground, it measures naturally occurring electromagnetic fields generated by solar and atmospheric activity across a frequency range of 25 to 20,000 Hz. The system uses differences in how these fields respond at depth to map the electrical resistivity of subsurface rocks.
Different rock types and mineralisation styles exhibit distinct electrical resistivity signatures. Furthermore, understanding these signatures is central to directing exploration activity effectively:
At Hasties, mineralisation is known to develop along a resistivity gradient — the boundary between resistive and conductive domains. The MobileMT survey has now imaged this gradient to depths exceeding 200 metres, revealing that the mineralised system continues well below the current drilling footprint.
High-quality geophysical surveys of this type reduce exploration risk by directing drillholes to the most geologically compelling targets. Rather than drilling on speculation, the Rincon Resources Telfer South depth target drilling plans can now be developed with a high-resolution 3D resistivity model as guidance, improving the probability of intersecting meaningful mineralisation at depth.
Before evaluating the new geophysical targets, it is important to establish the existing resource base at Telfer South. The Hasties MRE, announced in February 2025, provides a meaningful resource foundation across multiple cut-off grades.
| Cut-off (Au g/t) | Tonnes | Grade (Au g/t) | Grade (Cu %) | Contained Gold (oz) | Contained Copper (t) |
|---|---|---|---|---|---|
| 0.3 g/t | 870,000 | 0.96 | 0.26 | 26,800 | 2,286 |
| 0.5 g/t | 754,000 | 1.04 | 0.27 | 25,200 | 2,016 |
| 1.0 g/t | 235,000 | 1.86 | 0.28 | 14,100 | 654 |
Classification breakdown at the 0.3 g/t Au cut-off:
Rincon has indicated that exploration results from the MobileMT survey are expected to contribute to a future revision of the current MRE, though all required data is not yet available. This represents an important signal: if drilling confirms the depth extension identified by the survey, there is potential for material resource base growth.
The Telfer South Project operates within a broader strategic framework defined by two critical external factors.
The project is positioned 10 kilometres south of the Telfer Gold-Copper Mine in Western Australia's Eastern Pilbara. Telfer operates as a large-scale, long-running gold-copper operation, and the geological setting that hosts it extends southward into Rincon's tenure.
The Hasties mineralisation is interpreted to be associated with a significant anticline fold hinge zone, with steep-dipping structures controlling gold and fold structures controlling copper — consistent with the broader Telfer district mineralisation style.
Rincon's exploration at Telfer South advances under a multi-stage, multi-year Farm-In and Joint Venture agreement with Greatland Resources (ASX: GGP, AIM: GGP), announced in December 2025. The joint venture covers 200.8 km² of Rincon-owned exploration tenements, providing the project with both financial backing and a credible technical partnership as it advances toward drilling.
This structure enables Rincon to retain 100% ownership of its tenements while gaining support from a well-capitalised partner to advance exploration — a meaningful de-risking element for the project.
The MobileMT survey was conducted as a data-gathering exercise designed to refine and prioritise targets ahead of a planned RC drilling programme. Rincon's Technical Director has confirmed that the Rincon Resources Telfer South depth target drilling plans will be announced in the coming weeks.
According to the announcement, the following actions are underway:
The announcement of drilling plans in the near term represents the most immediate upcoming catalyst for Rincon shareholders.
| Upcoming Catalyst | Expected Timing |
|---|---|
| 2026 Drilling Program Announcement | Coming weeks |
| Close-spaced magnetic survey | To be confirmed |
| IP coverage expansion | To be confirmed |
| Ground truthing of additional anomalies | Coming months |
| Updated geological model | Ongoing |
Rincon operates at a critical inflection point. The MobileMT survey has transformed a project that already contained a defined gold-copper resource in a world-class mining jurisdiction, and has added a potentially significant depth dimension — one that remains entirely untested by drilling.
Several factors distinguish Rincon's position at this stage of the exploration cycle:
Rincon Resources has utilised a high-resolution geophysical survey to identify a significant, undrilled depth target directly beneath one of the Eastern Pilbara's most prospective gold-copper trends — just 10 km from the Telfer Mine. With a 26,800 oz Au resource already defined at surface, a Greatland Resources joint venture in place, and the Rincon Resources Telfer South depth target drilling plans imminent, Rincon approaches a pivotal development phase. Investors following the junior gold-copper exploration sector should monitor RCR closely as drilling plans are finalised in the weeks ahead.
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