Estrella advances Laleno copper target towards maiden drilling

Laleno Dome moves from theory to drilling

Estrella Resources Limited (ASX:ESR) is preparing to drill what it describes as Timor-Leste’s deepest hard-rock minerals exploration target, after surface sampling and petrographic work strengthened the case for porphyry-style copper-gold mineralisation at the Laleno Dome. Drill-site and access-track preparation has begun following approval of a maiden campaign after the September quarter.

“Location of Estrella Resources’ Timor-Leste concessions”

“Photomicrograph of a polished thin-section prepared from a sample of variably porphyritic diorite collected from 267485mE/9070652mN.”

Caption and image © Estrella Resources Limited. From “Quarterly Activities/Appendix 5B Cash Flow Report”, 29 Oct 2026.

The geological evidence is promising but remains early-stage. Rock-chip samples from the Laleno Dome included assays of up to 60.34% copper and 1.3 g/t gold, while samples taken from hydrothermally altered porphyritic diorite or microdiorite returned up to 0.66% copper. Petrographic analysis identified quartz-carbonate veinlets, silica flooding, chlorite-sericite alteration and disseminated pyrite, features the company says support an intrusion-related porphyry interpretation.

“The rock is hydrothermally altered with chlorite-sericite replacement of plagioclase and amphiboles (hornblende), along with silica flooding, carbonate replacement and presence…”

The result builds on Estrella’s Laleno porphyry copper findings, which previously identified copper-bearing porphyritic diorite and gold at multiple locations but still required drilling to test the system beneath surface. MobileMTd surveying has now highlighted several high-conductivity anomalies, including plume-like features rising from depth that may represent sulphide-bearing hydrothermal mineralisation. The company also cautions that some reported visual observations are not substitutes for laboratory assays.

Manganese sample approaches commercial test

At Ira Miri, Estrella has received approval to export an approximately 27,000-tonne manganese market-appraisal stockpile, including 4,984 tonnes of higher-grade material averaging 49.38% manganese. Approval has also been granted for a smaller trial parcel to travel overland to West Timor, with the customer responsible for haulage.

The export approval clears a key administrative hurdle, following the Ira Miri export authorisation reported earlier in October. It does not yet turn the stockpile into booked revenue: Estrella said execution of the sales agreement remains to be finalised, and the market-appraisal shipment will test customer and logistics arrangements rather than establish ongoing commercial production.

Werumata resource gains higher confidence

Estrella’s Werumata limestone project also delivered a substantial classification upgrade after quarter end. The updated resource stands at 533Mt, comprising 274Mt Indicated and 259Mt Inferred, with 391Mt classified as Product 1 limestone at 83.9% acid neutralisation capacity. The Indicated component represents about 70% of the higher-quality Product 1 resource.

The upgrade gives the project a more defined technical base, although the resource is not an Ore Reserve and does not by itself establish an operating project. The change follows the Werumata resource upgrade, which moved material into the Indicated category after additional bulk-density work while reducing the total resource from the earlier 621Mt estimate.

Cash position leaves little room for delay

Estrella ended September with A$2.852 million in cash after spending A$1.652 million on exploration and evaluation and A$584,000 on operating activities. Its Appendix 5B calculation put available funding at 1.27 quarters, with no unused finance facilities reported.

The company said it expects proceeds from the Ira Miri stockpile sale and retains capacity to raise additional funds. It has also agreed to divest its Spargoville nickel rights for 20 million Astral Resources shares valued at $3 million, subject to conditions. That transaction, together with the manganese sale, could help support the Timor-Leste program, but neither provides certainty of near-term cash until completion and binding terms are secured.

Drilling becomes the next decisive test

“Location of the MTd survey, shown by an example of the resulting conductivity anomaly images.”

Estrella is expanding its Timor-Leste footprint through new Covalima and Oecusse exploration licences and has started a helicopter-borne MobileMT and magnetic survey across the Lautem and Baucau project areas. The immediate question, however, is narrower: whether drilling can connect Laleno’s striking surface copper occurrences and geophysical anomalies to a coherent mineralised system at depth.