The test work is being carried out on samples of the massive and semi-massive sulphides from the Hollandaire and Hollandaire West prospects.
Determining optimal process
It is aimed at determining the optimal copper extraction process for Cyprium’s methodology, which has leached copper rapidly into solution.
Primary leach solution (PLS) produced from the metallurgical column test-work has been processed in an electrowinning (EW) cell to produce cathode copper metal plates.
These were then stripped from the cathodes to complete the processing cycle through to its final product of high-purity copper metal plate.
“Very suitable for methodology”
Cyprium’s executive director Barry Cahill said: “We are pleased to have now completed a full metallurgical processing cycle starting from drilling the mineralisation, to crushing and leaching, and now plating copper as a proof of concept of our low-cost treatment methodology.
“This has all been done in less than six months of commencing the column test-work.
“The Hollandaire material is very suitable for our methodology and it has outperformed our initial expectations.”
As part of an agreement between a subsidiary of Cyprium and Musgrave an option has been granted by Musgrave to earn-in and joint venture for an 80% interest in the non-gold rights over the Cue project tenements.
Samples for the tests have come from a metallurgical diamond drill program of three holes for 320 metres into the mineralised envelope of Hollandaire.
Core samples were received at the metallurgical laboratory in September 2019 with drill core crushed, split and assayed for multi-element grades and composites then created for the Hollandaire and Hollandaire West deposits.
Rapid leach times
Results to date have produced exceptionally rapid leach times.
The effect of the very short leach times on a potential copper project decreases the size of the heap leach pads and consequently reduces the capital and operating cost requirements over the life of the operation.
Cahill said: “To produce such a clean copper plate of high purity so quickly is an extraordinary result.
“The parameters of the metallurgical test-work performed to date is forming part of the scoping study that is underway.
“Further samples will be taken in the next phases of drill programs, which will be used for further metallurgical test-work to continue the optimisation of our low-cost and efficient treatment method.”
Process flow sheet completed
Completion of the plating of copper from the PLS solution in an EW cell completes the process flow sheet for the extraction method of copper from the Hollandaire mineralisation.
This is an important milestone in aspirations to build a project at Cue.
Metallurgical test-work will now proceed to further optimise the process for the best outcome in terms of cost and efficiency that is possible.