TORONTO (miningweekly.com) – British Columbia-focused miner Copper Mountain Mining has recorded record output from its eponymous flagship asset in the third quarter ended September 30, beating analyst expectations.
Copper output totalled 17.7-million pounds, up 13% on the 15.7-million pounds in the second quarter, while gold output rose almost 15% to 6 417 oz and silver output climbed 12% to 79 290 oz.
Copper Mountain attributed the improved performance to an increased average mill throughput rate made possible with the short-term secondary crushing strategies that had been implemented and improved late in July.
These short-term strategies included using an increased powder factor in the mine's blasting to create more fines in the ore; continuing with a contract portable crusher at the primary crusher to crush more than 5 000 t/d of ore to minus two inches; and introducing the company’s own small portable crusher that was bought and installed at the coarse ore stockpile during the quarter.
These activities were aimed at creating between 12 000 t/d and 13 000 t/d of minus two inch ore feed for the semi-autogenous grinding (SAG) mill. In September, the average daily throughput of the SAG mill was 31 925 t/d.
The mill availability improved to 94.2% in September, which contributed to the 89.3% average for the quarter.
Mill throughput during the quarter improved to an average of 29 130 t/d, compared with 26 000 t/d for the first half of 2013, an increase of 12%.
The mill processed 2.7-million tonnes of ore at an average grade of 0.344% copper, compared with 2.5-million tonnes of ore for the three months ended June 2013. Mill recoveries were 87% compared with 85% for the first half.
Mining continued in both the Pit 2 and Pit 3 areas on plan and averaged about 154 300 t/d.
For the quarter, the mine shipped 32 840 wet metric tonnes of concentrate containing about 16.3-million pounds of copper, 5 967 oz of gold, and 69 427 oz of silver generating about $61.8-million in gross revenue.
Laurentian Bank Securities metals and mining analyst Christopher Chang said he believed the company had a materially better understanding of the challenging orebody and had implemented the proper near- and long-term strategies to effectively process the material.
“In our view, we believe the operational turnaround is under way and the worst is behind them,” he said in a note to clients.
The analyst noted, however, that uncertainty surrounding the company’s secondary crusher financing continued to overhang the shares.