Board Shakeup at Brightstar Amid Strong Metallurgical Results at Cork Tree Well

Exceptional Metallurgical Performance at Cork Tree Well

Brightstar Resources Limited (ASX: BTR) has unveiled highly encouraging metallurgical testwork results from its Cork Tree Well (CTW) gold deposit, part of the Laverton Gold Project in Western Australia. The Definitive Feasibility Study (DFS)-level testwork, conducted on samples from 2024 diamond drilling, demonstrated gold recoveries exceeding 90% across all rock types and oxidation states, including oxide, transitional, and fresh mineralisation.

The metallurgical program, managed by independent consultants Independent Metallurgical Operations Pty Ltd (IMO), confirmed that both dolerite-hosted and sediment-hosted (shale and chert) mineralisation respond well to a conventional Carbon in Leach (CIL) processing flowsheet. Gravity recoverable gold was notably high, ranging between 25% and 60%, which bodes well for efficient gold extraction and processing economics.

Robust Processing Parameters and Low Impurities

Testwork optimized processing parameters at a grind size of P80 106 microns with leach residence times of 24 to 48 hours. Recoveries remained consistently strong, with 48-hour CIL recoveries ranging from 94% to 98% across lithologies. Importantly, the samples exhibited low levels of deleterious elements such as arsenic, antimony, and tellurium, which typically complicate gold recovery. This suggests minimal processing challenges and potential cost efficiencies.

Comminution testing revealed a range of ore hardness from medium to hard, with some composites classified as abrasive. These insights are critical for designing the processing plant and estimating operational costs accurately.

Accelerated Drilling to Expand Resource Base

Buoyed by these positive metallurgical outcomes, Brightstar is expediting a reverse circulation (RC) drilling program at Cork Tree Well, targeting the dolerite-hosted mineralisation at the Delta pit. This program aims to infill existing resources and explore high-grade plunging lodes beneath shallow historic pits, potentially adding significant oxide and transitional material to the DFS.

Meanwhile, metallurgical testwork continues on other key deposits within the Laverton and Jasper Hills projects, with results expected in the coming months. These ongoing studies will further refine the DFS and support mine planning and processing plant design.

Corporate Update: Board Change

In a notable board development, Non-Executive Director Matthew Bowles has resigned effective immediately to pursue other fulltime opportunities within the Australian natural resources sector. Mr Bowles joined Brightstar’s board in December 2024 following the Alto Metals merger and contributed significantly during the integration phase. The company expressed gratitude for his service and wished him well in his future endeavours.

Strategic Outlook

Brightstar’s Managing Director, Alex Rovira, highlighted the significance of the metallurgical results, emphasizing the strong recoveries across all rock types and the rapid leach kinetics. He noted that these outcomes underpin the company’s confidence in advancing the DFS and accelerating development timelines. The integration of geotechnical, mining, processing, and tailings storage facility designs is progressing in parallel, aiming to deliver a technically robust and capital-efficient project.

With a consolidated portfolio spanning Laverton, Menzies, and Sandstone hubs, Brightstar is positioning itself for staged development to become a meaningful ASX-listed gold producer. The latest metallurgical success at Cork Tree Well adds a critical piece to this growth puzzle.