VANCOUVER (miningweekly.com) – The value of the recent acquisition of two African zinc assets from mining major Glencore is evident in zinc-focused miner Trevali Mining's latest operating results, which it published on Monday, accounting for about 65% of output.

However, the company’s TSX-listed equity on Tuesday fell as much as 6.4% to C$1.47 a share, after investors saw the operating results as a miss.

Nevertheless, Trevali reported a consolidated record quarter for zinc production, recording payable output of 58.43-million pounds of zinc, compared with 13.66-million pounds a year earlier.

Lead output doubled year-on-year to 12.47-million pounds, up from 6.44-million pounds in the comparable period of 2016, while silver production also doubled to 433 442 oz in the third quarter.

The company’s improved performance was driven by a strong quarter at the Santander mine, in Peru, where mine and mill output increased by 23% and 7%, respectively, from the second quarter. Zinc head grades increased 12% and payable metal units have increased 21% for zinc, 29% for lead and 7% for silver, compared with the prior quarter.

The mill achieved the highest throughput, 20% above the 2 000 t/d nameplate capacity.

At the Caribou mine, in New Brunswick, Trevali continued to experience challenges during the quarter, producing significantly less than market forecasts. Caribou missed on tonnes milled and management has reduced the 2017 zinc guidance downward from 90-million pounds to 93-million pounds of payable metal, to 81-million to 84-million pounds of payable metal, leaving lead, silver and cash cost guidance unchanged.

At Perkoa, in Burkina Faso, the company recorded lower-than-expected output owing to lower zinc recoveries.

The Rosh Pinah mine, in Namibia, disappointed on grade, which was 7% zinc in the period, compared with consensus estimates calling for 9.5% zinc.