Great Boulder Resources Ltd: High Gold Recovery at Mulga Bill Drives Optimism

Key Highlights

• Metallurgical tests at Mulga Bill yield gold recoveries of up to 98.7%.
• Results confirm amenability to conventional gravity recovery and cyanide leaching methods.
• Side Well Gold Project’s Mineral Resource Estimate stands at 668,000 oz @ 2.8 g/t Au.
• GBR advances de-risking milestones toward potential mine development.

Great Boulder Resources Ltd (ASX: GBR) has unveiled impressive metallurgical test results from its flagship Side Well Gold Project near Meekatharra, Western Australia. With gold recoveries of up to 98.7% and low cyanide-soluble copper content, these findings mark a significant milestone for the development of the Mulga Bill deposit, the cornerstone of the Side Well project.

Transformative Metallurgical Insights

Metallurgical testing, conducted by Independent Metallurgical Operations Ltd (IMO), assessed five representative samples from Mulga Bill, focusing on gravity recovery and cyanide leaching efficiency. Highlights include:

• Gravity Recovery: High gravity recovery of 82.5% from the Star-Cervelo oxide sample, with other samples achieving recoveries ranging from 24% to 75.6%.
• Cyanide Leaching: Exceptional total recoveries, averaging 97.5% after 48 hours at a 75µm grind size.
• Low Cyanide-Soluble Copper: Tests revealed minimal impact of copper on gold recovery, with most samples exhibiting low levels of cyanide-soluble copper, reducing potential interference with leaching processes.

Andrew Paterson, Managing Director of Great Boulder Resources (ASX: GBR), emphasized the importance of these results: “This breakthrough de-risks Mulga Bill significantly. With proven compatibility with existing gold mills in the Meekatharra region, we’re now more confident than ever in advancing Side Well toward commercial production.”

Strategic Importance of Mulga Bill

The Mulga Bill deposit, which hosts the majority of the 668,000 oz Mineral Resource Estimate at Side Well, is critical to GBR’s development plans. Key features include:

• High-Grade Gold Potential: Drill samples revealed grades up to 31 g/t Au in fresh rock.
• Resource Versatility: Tested samples span various mineralization styles, including gold supergene, gold-copper supergene, and high-grade oxide zones.
• Minimal Environmental Constraints: The project’s reliance on industry-standard leaching methods minimizes environmental risks and simplifies permitting processes.

A Step Closer to Development

The metallurgical success at Mulga Bill paves the way for further optimization and resource development. GBR’s next steps include:

• Flowsheet Optimization: IMO will refine the metallurgical process, focusing on reagent use and grind size.
• Blending Studies: Further testing will optimize recovery rates for lower-grade and copper-rich ore types.
• Exploration Expansion: GBR plans additional drilling at Side Well to expand the resource base and enhance project economics.

Market Performance and Outlook

GBR shares closed at $0.045 on January 15, 2025, reflecting a 4.26% decline. Over the past year, the company’s stock has faced headwinds, with a 25% annual drop. However, the company’s YTD performance shows a 4.65% gain, supported by recent technical achievements and robust project potential.

Market Snapshot

• Market Cap: $34.16 million.
• Shares Issued: 759.1 million.
• 52-Week Range: $0.040 - $0.069.

Positioning for Long-Term Success

Great Boulder Resources’ (ASX: GBR) focus on systematic exploration and technical innovation positions the company as a promising player in Western Australia’s gold sector. The Side Well project, with its substantial resource base and metallurgical viability, offers significant upside potential as GBR progresses toward feasibility studies and production readiness.