Brightstar Resources (ASX: BTR) has increased the Mineral Resource Estimate (MRE) at its Menzies gold project following infill and extensional drilling undertaken during 2025, delivering a 22% increase in total contained gold to 0.7 million ounces at 1.5 grams per tonne.
The upgraded estimate also strengthens the company’s broader Mineral Resource base, which now exceeds 4Moz at 1.5g/t across the Goldfields and Murchison regions.
Drilling completed across the Lady Shenton System and Yunndaga deposits has delivered substantial growth in both scale and confidence, with the Yunndaga resource increased by 32% to 206koz at 2.1g/t gold and the Lady Shenton System lifting by 29% to 352koz at 1.4g/t.
Indicated material rose sharply at both deposits, with Yunndaga increasing 187% to 152koz and Lady Shenton 37% to 168koz.
Mineralisation remains open along strike and at depth at both locations, indicating strong potential for additional resource growth, with the company noting that several other deposits and prospects at Menzies remain underexplored, providing further upside for future drilling campaigns.
Improved Geological Confidence
Infill reverse circulation and diamond core drilling at Yunndaga tightened spacing across key zones and delivered new geotechnical and metallurgical data.
Brightstar said these datasets would support the maiden declaration of Ore Reserves in parallel with an updated definitive feasibilty study (DFS).
Drilling incorporated both broad halo mineralisation and high-grade domains at Yunndaga, allowing refined modelling across ten mineralised lodes, while the updated modelling at Lady Shenton reflects extensive work across the Pericles, Lady Shenton and Stirling deposits to interpret multiple lodes with consistent structural controls.
Both resource models incorporated detailed geological logging, revised wireframes, and updated variograms to support estimation using ordinary kriging.
Near-Term Production Progress
Managing director Alex Rovira said the updated figures highlight the company’s progress toward near-term production.
“Not only have we increased the size of the overall MRE by 22%, we have also increased the Indicated component of the Yunndaga deposit by 187% and the Lady Shenton deposit by 37%,” he said.
“The Indicated resources at these two key proposed mining areas now exceeds 300koz gold, and will underpin updated mine plans and production metrics in the upcoming 'Goldfields DFS 2.0' due for release in Q1 CY26.”
Brightstar’s work since the June 2025 feasibility study has continued to de-risk the Menzies and Laverton projects as it advances permitting and funding activities, with the company expecting to finalise updated mine plans, schedules, budgets, and economic models ahead of its targeted Final Investment Decision in the first quarter of 2026.
Broader Goldfields Inventory Growth
The Menzies upgrade contributes to Brightstar’s consolidated mineral resource base of 4.0Moz at 1.5g/t across its combined hubs.
The company reported recent increases across several Laverton and Sandstone deposits including key assets such as Lord Byron, Two Mile Hill, and the Vanguard and Havilah camps.
Brightstar said resource expansion across multiple tenements reflects the benefits of ongoing drilling, data consolidation, and modelling improvements it has completed since its series of acquisitions and mergers.
The company plans further drilling and evaluation work across the Goldfields Hub into 2026 as it prepares the Menzies and Laverton projects for development, and its growth strategy includes both open pit and underground mining options supported by ongoing metallurgical test work and processing studies.
