Great Boulder Resources reports outstanding gold recoveries of up to 96% at Mulga Bill with significantly reduced cyanide levels, promising lower processing costs and capital expenditure. The Ironbark scoping study is progressing well, with further drilling underway to expand resources.
- Gold recoveries between 92% and 96% achieved at Mulga Bill with cyanide at 150ppm
- Coarse grind sizes (75µm to 150µm) maintain consistently high gold recovery
- Reduced cyanide consumption could lower processing and capital costs
- Ironbark scoping study on track for completion this quarter
- Ongoing drilling at Eaglehawk and Side Well South to expand resource base
Metallurgical Breakthrough at Mulga Bill
Great Boulder Resources (ASX: GBR) has unveiled promising metallurgical test results from its Mulga Bill deposit within the Side Well Gold Project in Western Australia. A second round of test-work confirms that gold recoveries remain impressively high, ranging from 92% to 96%, even when cyanide concentrations are significantly reduced to 150ppm. This finding is particularly notable given the environmental and cost implications of cyanide use in gold processing.
The tests, conducted by Independent Metallurgical Operations Pty Ltd (IMO), also reaffirm that a relatively coarse grind size between 75µm and 150µm does not compromise recovery rates. This combination of low cyanide consumption and coarse grinding suggests potential for streamlined processing with lower capital expenditure, as smaller or fewer leach tanks may be required.
Strategic Implications for Processing and Costs
Great Boulder’s Managing Director, Andrew Paterson, highlighted the significance of these results, noting that reduced cyanide use coupled with coarse grinding could translate into faster leaching and reduced processing costs. This is a critical consideration for the company as it advances engineering studies and contemplates the construction of a stand-alone processing plant for the Mulga Bill deposit.
Such metallurgical efficiencies could enhance the economic viability of the deposit, which currently holds a Mineral Resource Estimate of 668,000 ounces at 2.8 g/t gold. The potential to lower both operating and capital costs aligns well with Great Boulder’s broader strategy to develop high-grade feed sources and expand its resource base.
Ongoing Exploration and Study Progress
Beyond Mulga Bill, Great Boulder is actively progressing its Ironbark scoping study, with results expected by the end of May. This study will provide further clarity on the project’s development pathway. Meanwhile, drilling campaigns continue at Eaglehawk, where 19 aircore holes have been recently completed and are currently being assayed, and at Side Well South, where reverse circulation drilling is following up on earlier gold discoveries.
These exploration efforts underscore the company’s commitment to growing its resource inventory and advancing multiple prospects within the Side Well Gold Project. The combination of robust metallurgical performance and active drilling programs positions Great Boulder well for the next phases of project development.
Environmental and Operational Considerations
Reducing cyanide consumption not only offers cost benefits but also aligns with increasing environmental scrutiny on mining operations. Lower cyanide levels can mitigate risks associated with chemical handling and waste management, potentially easing regulatory approvals and community concerns. Great Boulder’s metallurgical results thus carry implications beyond economics, touching on sustainability and operational resilience.
As the company moves forward, the integration of these metallurgical insights into feasibility and engineering studies will be key to unlocking value and ensuring efficient, responsible project execution.
Bottom Line?
Great Boulder’s metallurgical advances at Mulga Bill could reshape its processing strategy, with cost and environmental benefits setting the stage for upcoming resource and study updates.
Questions in the middle?
- How will the reduced cyanide consumption impact overall project economics and capital requirements?
- What are the expected timelines and potential outcomes of the Ironbark scoping study?
- Can ongoing drilling at Eaglehawk and Side Well South significantly expand the current resource base?