Chalice Mining lifts Gonneville metal recoveries with breakthrough flowsheet improvements
Chalice Mining (ASX: CHN) has achieved further success with its plans to develop the highly regarded Gonneville critical minerals project in Western Australia.
New flowsheet improvements at Gonneville have delivered significant increases in metal recoveries achieved from flotation and CIL leach processes.
The test work has also identified a potential new iron by-product.
Step-changes achieved
“These cumulative improvements in recoveries, operating costs and now potentially a new iron by-product, represent likely game-changers for the world-class Gonneville project,” chief executive officer Alex Dorsch said.
“As expected, given the unique scale and polymetallic nature of the Gonneville deposit, it was going to take some time to fully understand and extract maximum value from the process flowsheet.”
“We have now established a far superior flowsheet that opens up a bulk open-pit mine plan with a very low strip ratio, at bottom-of-the-cycle metals prices.”
“This means we have further improved the competitiveness of the asset and reduced the incentive price levels required to develop the project.”
Metallurgical breakthrough
The promising new results back up the metallurgical breakthrough and flowsheet simplification the company announced in mid-February 2025.
Chalice has now completed test work and mass balances on all Gonneville sulphide mine composites, with a further improvement in overall recoveries confirmed.
The company believes the latest optimisations will further enhance margins at the project from those laid out in its 2023 scoping study.
It is also continuing work on ways to commercialise the by-product and generate a potential new source of revenue for Gonneville.
PFS well-advanced
Chalice chief operating officer Dan Brearley said the company was quickly advancing the Gonneville pre-feasibility study (PFS) in terms of processing and mining parameters.
The company is now focusing on finalising plant capital and operating costs, quantifying the iron by-product and identifying the options available and supporting infrastructure costs.
“There are no significant technical impediments remaining to developing this project [and] environmental modelling based on the preferred staged development case is now well underway ahead of full-form regulatory submissions early next year,” Mr Brearley said.
“We have secured very strong support from government at all levels, which gives us confidence there is a clear pathway to securing all approvals in a timely manner.”