Yunndaga Drilling Success Raises Stakes for Brightstar’s Resource Expansion Risks

Strong Drilling Results at Yunndaga

Brightstar Resources Limited (ASX: BTR) has unveiled final assay results from its Phase 1 reverse circulation drilling campaign at the Yunndaga deposit, part of the Menzies Gold Project in Western Australia. The program, spanning approximately 6,100 metres, targeted infill and extensional zones within a deposit that currently holds a 0.6 million ounce resource at 1.4 grams per tonne gold.

Among the standout results is a 16-metre intercept grading 8.03 grams per tonne gold starting from 220 metres depth, including a high-grade 1-metre section at 33.6 grams per tonne. Other significant intercepts include 13 metres at 4.7 grams per tonne and 11 metres at 3.32 grams per tonne, all reinforcing the presence of robust mineralisation beneath the existing open pit.

Implications for Underground Mining

The drilling results affirm the potential for a substantial underground mining operation at Yunndaga. Historical mining in the area produced over 270,000 ounces at exceptionally high grades exceeding 16 grams per tonne, with workings extending beyond 600 metres depth. Brightstar’s current underground mine designs, based on a 2023 scoping study, focus on the upper 200 metres, but the deposit remains open at depth, suggesting further upside potential.

Managing Director Alex Rovira expressed enthusiasm about the results, highlighting the consistent high-grade zones intersected and the company's confidence in advancing Yunndaga as a near-term underground opportunity alongside its Lady Shenton open pit project.

Next Steps and Broader Exploration

Building on the success of Phase 1, Brightstar plans a second drilling phase commencing in June 2025, involving both reverse circulation and diamond drilling. This phase aims to extend mineralisation at depth and improve resource confidence to support future mine planning and Ore Reserve declarations by late 2025.

Beyond Yunndaga, Brightstar continues to advance exploration across its portfolio, including the Fish Deposit at the Laverton Hub and the Sandstone Gold District, where a prefeasibility study is targeted for the first half of 2026. The company’s integrated approach seeks to leverage multiple assets to underpin sustainable production growth.

Technical Rigor and Historical Context

The drilling program employed industry-standard sampling and assay protocols, with quality control measures ensuring reliable data. The geological setting is typical of Archean mesothermal lode gold deposits, with mineralisation hosted in shear zones within metamorphosed mafic and ultramafic rocks. The results align with historical data and previous mining, providing a solid foundation for resource expansion.

Brightstar’s systematic exploration and resource definition efforts at Yunndaga and surrounding projects underscore its commitment to unlocking value in Western Australia’s prolific goldfields.