Mining companies will invest some $13.1 billion in copper and gold projects in Chile through 2010, Cochilco, Chile's government copper commission, said Tuesday.

As a result, copper production will increase to 6.2 million metric tons in 2010, up from 5.3 million tons in 2005.

The South American country is the world's biggest producer of the metal, mining 35.5% of global output last year.

Of the projected $13.1 billion in investments, state copper giant Corporacion Nacional del Cobre de Chile's, or Codelco, investments represent slightly more than 50% of total investments during the five-year period, said Cochilco market analyst Vicente Perez.

Codelco plans to invest $6.6 billion during 2006-2010, with the bulk of that investment going to expanding output at its Norte division and bringing the Gaby deposit on line.

Private-sector investments include expansions at Antofagasta's (ANTO.LN) Los Pelambres mine, Anglo-American's (AAUK) Los Bronces mine, and the BHP Billiton-controlled (BHP) Escondida mine.

The lion's share of both private and state copper investments is earmarked for expansions at existing mine, in order to prolong their lifespans.

Investments in new projects, meanwhile, are falling as no new "mega-deposits" have been discovered, said Cochilco analyst Algo Picozzi.

"All of the new projects coming on line are expected to produce around 180,000 tons of copper a year," Picozzi said.

Gold project investments, meanwhile, include Barrick Gold Corp.'s (ABX) Pascua-Lama and Bema Gold Corp.'s (BGO) Cerro Casale.

"Cerro Casale is still an uncertain project, but we opted to include it in our study," Perez said.

With the Pascua-Lama and Cerro Casale projects on-line, Chile would produce 100 metric tons of gold a year, from its current 40 ton-per-year output, according to Perez.

Amid strong demand from Asia in particular, mining companies have reaped the benefits from surging commodities prices.