08:30 AM EST, 01/18/2018 (MT Newswires) -- Sierra Metals, (SMT.TO), the Latin American miner whose shares have risen by more than half over the past year, said on Thursday weaker fourth quarter production of silver, lead and gold was offset in part by higher zinc and copper output as it released its 2018 guidance.

The company, which operates mines in Mexico and Peru, said it produced 496,000 ounces of silver in the quarter, down 37% from the year-prior period, while lead output fell 43% to 5.7 million pounds and gold production dropped 15% to 1,591 ounces. However the company's output of copper rose 21% to 7.5 million pounds and zinc production at 19.5 million pounds was 15% above the fourth quarter of 2016.

Sierra said the changes were due to changes in mine throughput and poorer ore grades for its Mexican operations, where it has launched a program to improve output and lower costs.

For 2018, the company is targeting output of between 13,900 and 16,210 silver-equivalent ounces from its mines, from 14,865 in 2017.

Sierra is budgeting $49 million for capital projects this year, including $35.7 million for exploration and expansion projects and $13.1 million in sustaining capital.

Sierra share, which have risen 54% over the past 12 months, closed Wednesday at $3.24 on the Toronto Stock Exchange, within the 12-month trading range of $2.05 and $3.75.