Kin Mining NL (ASX:KIN) has recovered up to 96.9% gold during test-work on ore from its 1.275-million-ounce Cardinia Hill camp near Leonora in Western Australia.
The company used flotation, re-grinding and leaching techniques to recover the gold from some of the project’s sulphide ores.
Today, Kin said the method saw better gold recoveries compared to conventional test-work methods, boosting the recoveries by 6.3% at Cardinia Hill and by 10.9% and up to 12.6% at the Helens and Lewis prospects.
As a result, metallurgical recovery is likely to be around 97% for Cardinia Hill sulphide ores (based on optimal conditions test-work), 91% for Helens and 87% for Lewis sulphide ore (going off the sighter test-work to date).
Down the line, further test-work programs are likely as drilling penetrates deeper sulphide-dominant ores at Cardinia’s Rangoon, Fiona and Helens East deposits.
“Important outcomes”
Commenting on the test-work results today, Kin Mining managing director Andrew Munckton said: “The metallurgical test-work program undertaken on sulphide ore from key Cardinia deposits has delivered some very positive and important outcomes for the Cardinia Gold Project.
“Importantly, the test-work has confirmed that strong gold recoveries can be achieved with flotation, re-grinding and leaching of the sulphide ores.
“These results indicate that sulphide ores from Cardinia, if treated using the flotation and re-grind process, are likely to result in significantly improved gold production and financial returns.
“As our exploration programs advance, particularly across the Eastern Corridor, we are continuing to discover significant extensions of this large mineralised system – particularly deeper, higher grade sulphide ores.”
Munckton also said the process selected to treat these sulphide ores — and the resulting metallurgical performance — will be increasingly important.
“Oxide ores that lie near-surface and above the sulphide ores show uniform high rates of metallurgical recovery, ranging from 90.5% to 95.5%, using the conventional grind, gravity and leach process,” he explained.
Test-work program
Kin embarked on metallurgical recovery and sighter test-work across the Cardinia Hill, Helens and Lewis targets.
The metallurgical test-work program was designed to confirm the most cost-effective processing route for each ore type confirmed within the large, rapidly developing Western and Eastern Corridor mineralised complex, which make up the Cardinia area.
Mineralisation discovered at Cardinia extends over roughly 1 kilometre by 5 kilometres on the western and eastern side of the gold camp.
Cardinia also contains a number of development prospects, including Cardinia Hill, Helens, Bruno, Lewis, Fiona, Rangoon and East Lynne, which collectively contain more than 650,000 ounces of gold in mineral resources.
All eyes on the Eastern Corridor
The latest test-work results have focused Kin’s attention on one area of promise at Cardinia: the Eastern Corridor.
Munckton said the company was already honing in on the target thanks to a spate of strong drill results out of the Rangoon, Cardinia Hill and Helens East prospects, where sulphide intersections at depth were significantly higher in grade.
Coupled with the strong recovery results from Cardinia Hill and Helens, he said the Eastern Corridor was shaping up as a “significant centre for development” at the Cardinia Gold Project.
“The Eastern Corridor is proving to be highly mineralised, with numerous deposits and mineralised positions already identified,” Munckton explained.
“We see significant potential to discover new high-grade lodes, delineate new resources and grow our overall inventory across this corridor.
“Strong metallurgical performance from these deposits gives confidence that the Eastern Corridor and the Cardinia area more generally will continue to be a big focus for us moving forward.”