First Quantum produced 107,808 tonnes of copper in the quarter, up 4 percent from the same period a year ago, and copper sales jumped 20 percent to 114,449 metric tons. Nickel production rose 12 percent to 12,223 tonnes.

The Vancouver-based company, which primarily mines copper but also produces nickel and gold, said earnings attributable to shareholders rose to $133.6 million, or 23 cents a share, in the second quarter, from $71.9 million, or 12 cents, a year earlier. Sales revenues rose to $945.1 million from $869.3 million.

Excluding unusual items, earnings in the year-earlier quarter were $103.6 million, or 18 cents a share.

The company, which took over rival Inmet Mining last year, gaining control of the huge Cobre Panama project, is poised to become one of the world's largest copper producers over the next five years, with a number of projects, including Cobre Panama in Central America, set to begin production.

Analysts, on average, had expected First Quantum to report earnings of 26 cents a share, according to Thomson Reuters I/B/E/S.

(Reporting by Allison Martell in Toronto; Editing by Tom Brown and Andre Grenon)