Ongoing metallurgical tests conducted for Vancouver-based Kutcho Copper Corp. on material from its Kutcho project 100 km east of Dease Lake, British Columbia show improved recoveries of copper, zinc and silver, higher concentrate grades, and improved separation of copper and zinc into concentrates.
The recent locked cycle tests were performed on material from the Esso lens that graded 2.6% copper, 5.5% zinc, 1 g/t gold and 70 g/t silver. The copper recovery to concentrate was 94.5% producing a concentrate that graded 27.9% copper and 4.45% zinc. The zinc recovery to concentrate was 89.3%, producing a concentrate that graded 58.2% zinc and 0.62% copper.
Earlier metallurgical tests done for the prefeasibility study recovered 84.7% of the copper and 75.7% of the zinc.
The flowsheet used for the Esso lens material was the same as the one used for testing material from the Main lens in September. The current flotation plant design has a single cleaner step in the copper circuit and two cleaner steps in the zinc circuit. While the copper cleaner product required regrinding, the zinc cleaner product did not.
Kutcho Copper will use the results of the recent tests as part of the feasibility study for a mine and mill at Kutcho.
(This article first appeared in the Canadian Mining Journal)