Cobalt Blue Holdings Ltd (ASX:COB) has used its COB Process to recover cobalt, copper and gold concentrates from Global Energy Metals Corporation (CVE:GEMC) (OTCMKTS:GBLEF) Millennium Project in northwest Queensland.
The processing technology developed by COB achieved “excellent” metal recoveries and CEO Joe Kaderavek said the results were “significant” for the business.
He said: “We have used the COB Process to successfully recover cobalt, copper and gold from mineralisation typical of Queensland’s Mount Isa-Cloncurry district.
“Whilst our focus remains on our core Broken Hill Cobalt Project, these results underpin strong optionality for our business.”
GEMC provided a 70 kilogram mineralised sample to COB for the test-work.
COB developed a successful flotation scheme to produce two separate copper and cobalt concentrates.
Total flotation recovery of metals to concentrates achieved was 93% cobalt, 93% copper and 80% gold.
Concentrate grades and recoveries.
COB Process used
The cobalt concentrate was then treated using the COB Process.
Step one saw thermal decomposition of the pyrite, where all the pyrite was converted to pyrrhotite.
In step two the resulting calcine (pyrrhotite) was leached to extract cobalt and copper.
The process successfully treated the cobalt concentrate with leach extractions of 90% of the cobalt and 95% of the copper.
On account of the formation of gold-chloride complexes, 10% of the gold was also leached into solution.
The leach residue was filtered and washed, and then subjected to a further cyanide leach to recover free gold.
Total gold extracted from the cobalt concentrate was 90% with 10% in the chloride leach and a further 80% in the cyanide leach.
Total gold recovery was 90%.
Detailed results from the test program are now being evaluated.
Other Queensland applications
This test-work has potential application to other Queensland cobalt deposits, with the State Department of Natural Resources, Mines and Energy announcing new initiatives to explore for ‘new economy minerals’ including cobalt.
This incorporates a program managed by the Geological Survey of Queensland and The University of Queensland to evaluate cobalt in tailings of substantial copper mines in the North West Minerals Province, including the Mount Isa-Cloncurry district.
Results from the Millennium test-work indicate that the COB Process could be successfully adapted to treat cobalt-copper-gold sulphides prevalent in the resource-rich district.
COB has also been engaged by OZ Minerals Limited (ASX:OZL) (OTCMKTS:OZMLF) to conduct amenability testing of the COB Process on a pyrite concentrate containing cobalt, gold and copper from the Carrapateena project in South Australia.
A sample of the concentrate has been received by COB, with extensive test-work expected to take four months to complete.