Refining the metallurgy at Kutcho Copper
North of 60 Mining News – October 19, 2018
Last updated 9/25/2020 at 6:51am
Kutcho Copper Corp. Oct. 18 said the latest round of drill results at its namesake project in northern British Columbia have confirmed the high-grade mineralization in the Main deposit and is providing material for metallurgical work needed to advance the Kutcho Copper project to the feasibility level.
Located about 100 kilometers (60 miles) east of Dease Lake, the Kutcho property hosts three known Kuroko-type volcanogenic massive sulfide deposits along an east-west trend. The largest, Main, comes to surface at the east end of the trend, with Sumac and Esso each getting deeper to the west.
A prefeasibility study updated at the time of the acquisition considers the development of a 2,500-metric-ton-per-day operation that would produce 378 million pounds of copper and 473 million lb of zinc, plus by-product precious metals over a 12-year mine life.
This operation is based on 10.4 million metric tons of probable reserves averaging 2.01 percent copper, 3.19 percent zinc, 0.37 grams per metric ton gold and 34.61 g/t silver.
As part of the PFS, the explorer conducted a detailed review of cut-off grade sensitivities that resulted in a cut-off grade of 1 percent copper being selected for reporting mineral resources, compared to 1.5 percent previously contemplated. The lower cut-off grade increases the measured and indicated mineral resource tonnage by 49 percent and the inferred mineral resources tonnage by 432 percent, with only a 13 percent and 24 percent in copper-equivalent grade, respectively.
Due to this adjustment, there is a large portion of resources in the Kutcho Copper deposits that can be upgraded to higher confidence categories and potentially reserves.
With the goal of advancing this project to the feasibility stage by the end of 2019, this year's program includes additional geotechnical work on the deposits; a drill program to upgrade a portion of the inferred mineral resources to the measured and indicated categories, which could then be converted to reserves when the feasibility study is completed; additional metallurgical work; and environmental baseline studies.
The latest batch of drill results are from 14 holes – KC18-235 to KC18-248 – targeted primarily to collect metallurgical samples across Main deposit. These holes intersected all styles of mineralization, including exhalative, semi-massive and massive sulfide mineralization.
The material collected in these holes has been sent to a lab for metallurgical analysis designed to refine and build on previous studies conducted by Capstone. This bench scale test program will define anticipated recoveries and concentrate grades and will guide design parameters required for the mill design.
While primarily targeted for this metallurgical work, the assay results from these holes also help affirm the confidence in the resource model for Main deposit.
Highlighted assay results from this drilling include:
• 15.6 meters of 2.58 percent copper, 3.7 percent zinc, 56.7 g/t silver and 0.65 g/t gold in KC18-235;
• 12.6 meters of 2.17 percent copper, 2.1 percent zinc, 38.9 g/t silver and 0.38 g/t gold in K18-243;
• 34.2 meters of 2.17 percent copper, 1.4 percent zinc, 35.7 g/t silver and 0.38 g/t gold in K18-245; and
• 10.4 meters of 3.44 percent copper, 3.3 percent zinc, 48.1 g/t silver and 0.52 g/t gold in KC18-247.
"These drill holes continue to confirm the high-grade nature of mineralization at the Main deposit," said Kutcho Copper President and CEO Vince Sorace. "We have now commenced our metallurgical program and continue to drive forward with all elements of the feasibility study, which remains on time, and on budget."