North of 60 Mining News - The mining newspaper for Alaska and Canada's North

Pebble Partnership copper gold molybdenum mine project Alaska Northern Dynasty NAK NDM

By Shane Lasley
Mining News 

High grades boost Silvertip, Kensington

BC mine silver output up 44%, gold up 15% at SE Alaska mine

 

Last updated 7/26/2019 at 5:22am

Coeur Mining Inc.

An aerial view of Silvertip Mine in northern British Columbia. Increasing the production of silver, zinc and lead at this high-grade operation is a top 2019 initiative for Coeur Mining.

Increased ore grades and improved recoveries bolstered metals production at Coeur Mining Inc.'s two northern operations – the Silvertip silver-zinc-lead mine in northern British Columbia and the Kensington gold mine in Southeast Alaska.

Since achieving commercial production at its newly acquired Silvertip Mine last September, Coeur has been focused on increasing throughput, recoveries and grade at this operation just south of the Yukon border.

These endeavors have resulted in sharp increases in all three metals produced.

During the second quarter of 2019, Silvertip produced 344,000 ounces of silver, a 44 percent increase over the 239,000 oz produced during the first three months of the year; 5.3 million pounds of zinc, up 43 percent compared to the 3.7 million lb produced during the previous quarter; and 5.2 million lb of lead, a sharp 62 percent rise over the 2.7 million lb recovered during the previous three months.

The increased metals output at Silvertip was driven by significantly higher-grade ore, as well as improved mill recoveries.

The average silver grade during the second quarter was 7.5 oz per ton, compared to 5.5 oz/t during the first three months. At the same time the mill recovered 77 percent of the silver in the ore, compared to 69.9 percent during the previous quarter.

Likewise, quarter-over-quarter zinc grades improved from 5.9 percent to 7.5 percent and recoveries improved from 50.5 percent to 59.1 percent; and lead grades improved from 3.7 percent to 5.4 percent and recoveries improved from 66.8 percent to 77.3 percent.

Mill throughput, however dropped about 4 percent, from 62,051 tons in the first quarter to 59,689 tons in the second.

The roughly 656-ton-per-day production rate at Silvertip is expected to increase over the course of this year as Coeur continues to execute key projects targeting mill availability.

"We continue to deliver quarter-over-quarter improvements at Silvertip, which is a top initiative for the company this year," said Coeur Mining President and CEO Mitchell Krebs.

Coeur has applied for an amendment to its Silvertip permits to increase production at the mine to 1,100 metric tons per day on a regular basis. Approval of the amendment, which was anticipated by now, is now expected before the end of September. The company said this delay does not impact its plans for Silvertip.

The Chicago-based miner continues to forecast the Silvertip Mine to produce 1.5 million to 2.5 million oz of silver, 25 million to 40 million lb of zinc and 20 million to 35 million lb of lead this year.

Much like its high-grade silver neighbor in B.C., the Kensington Mine in Alaska experienced a strong quarter due to increased grades and improved recoveries.

Kensington produced 34,049 oz of gold during the second quarter of this year, which is 14 percent higher than the 29,973 oz recovered at the underground gold operation during the first three months of 2019.

This increase is largely due to more higher-grade ore from the Jualin Mine being fed into the mill.

Going into 2019, Kensington (including Jualin) had 2.59 million tons of proven and probable reserves averaging 0.213 oz per ton (552,000 oz) gold.

In comparison, Jualin alone hosted 157,600 tons of ore averaging 0.47 oz/t (74,100 oz) gold, according to a maiden reserve calculation completed last year.

Roughly 17 percent of the second quarter production came from Jualin, compared to 10 percent from this newly commissioned mine during the first quarter. As a result, the average grade at the Kensington operation was 0.23 oz/t gold, compared to 0.20 oz/t during the first three months.

Jualin is expected to account for approximately 20 percent of Kensington's total 2019 production, indicating further increases from this mine over the coming months.

Second quarter recovery rates at Kensington also increased to 93 percent, from 90.2 percent in the first quarter.

Coeur Mining President CEO Kensington gold, Silvertip silver mines

Mitchell Krebs

Coeur continues to anticipate that the Kensington Mine will produce between 117,000 and 130,000 oz of gold this year.

The Chicago-based miner's five operations – Kensington, Silvertip, Palmarejo (Mexico), Rochester (Nevada) and Wharf (South Dakota) – produced 3.1 million oz of silver, 86,584 oz of gold, 5.3 million lb of zinc and 5 million lb of lead during the second quarter of 2019.

"Our second quarter operational results were in-line with our expectations and reflect solid, double-digit production increases across all four metals we produce," said Krebs. "Overall, we remain confident in our ability to achieve our full-year production guidance at each of our operations."

 

Reader Comments
(0)

 
 

Powered by ROAR Online Publication Software from Lions Light Corporation
© Copyright 2019