Brightstar’s metallurgical testing has achieved recoveries of more than 90% gold from Cork Tree Well. Pic: Getty Images
Brightstar testing achieves strong recoveries of more than 90% gold at Cork Tree Well
Mining
share
- Brightstar Resources’ metallurgical testing has achieved recoveries of more than 90% gold from its Cork Tree Well project
- Results across various mineralisation types indicates strong gold recoveries with low levels of deleterious elements
- RC drilling planned at Cork Tree by early March to test dolerite-hosted mineralisation at the Delta pit
Special Report: Detailed definitive feasibility study-scale metallurgical testing has returned excellent recoveries in excess of 90% gold from Brightstar Resources’ Cork Tree Well project near Laverton, WA.
The recoveries, which included high-gravity recoveries ranging from 25% to 60%, were returned from all rock types at the project including dolerite-hosted mineralisation at the Delta and Cork Tree Well North areas, and sediment-hosted mineralisation at Cork Tree Well South.
Notably for Brightstar Resources (ASX:BTR), the results were returned using lower range parameters set at a coarse grind of P80 106 µm for 24 hours leach, with upper range at identical grind for 48-hour leach residence time.
All testwork was also based on the company’s elected processing flowsheet with a simple and conventional carbon in leach circuit being optimised based on results to date using diamond holes drilled in 2024.
The testwork also highlighted low levels of deleterious elements, with minimal impact on metallurgical recoveries in all rock types.
“The results from our testwork program have proven that Cork Tree Well recovers exceptionally well across all rock types and oxidation states,” managing director Alex Rovira said.
“Material feeding the testwork programs were from our 2024 diamond drilling program, with comprehensive leaching and comminution testwork being assessed by our DFS metallurgical consultants, IMO.
“Based upon these positive results, we have elected to expedite an RC program at Cork Tree Well to commence by early March 2025, with the view of targeting dolerite-hosted mineralisation at the Delta pit to generate additional oxide and transitional material being assessed in the DFS.
“We look forward to sharing the completed metallurgical results for our remaining projects being studied within the DFS, with all sample material in the lab and being processed through the various testwork programs.
“In parallel with the metallurgy workstreams, our geotechnical and mining consultants are finalising the open pit and underground mine designs and schedules, our processing engineers are in the final stages of process plant design, and our TSF engineering consultants nearing completion on an in-pit tailings deposition solution for a technically robust and low capital tailings storage facility.”
Meanwhile, non-executive director Matthew Bowles has stepped down as a non-executive director with immediate effect to focus on other business interests.
Gold recoveries
The metallurgical testing achieved 90-98% recoveries in oxide mineralisation at Delta and Cork Tree Well North, 90-98% for transitional ore and 90-95% for fresh rock.
Over at Cork Tree South, recoveries of 91-96% and 90-94% for the fresh chert and shale respectively.
BTR added that testwork for the remaining projects is progressing well, with expected completion in the coming months for Lady Shenton (Menzies), along with the Fish and Lord Byron deposits (Jasper Hills) ~50km south-east of Brightstar’s processing plant site.
The company is also expediting the RC drill program focused on dolerite-hosted mineralisation at Delta, targeting high-grade plunging lodes below the shallow historical pits.
Ongoing technical workstreams are well progressed within the DFS while near-term development of mining operations at Jasper Hill is continuing.
Onsite activities at Jasper Hills includes haul road signage upgrades and preparation ahead of ore haulage from historical low-grade stockpiles.
This article was developed in collaboration with Brightstar Resources, a Stockhead advertiser at the time of publishing.
This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.
