Overall investments of mining firms in Peru reached $7.2 billion in 2011, representing a hike of 77 per cent over a year ago, data from the country's Mines and Energy Ministry showed.

Of the total figure, $1.39 billion were spent on infrastructure, $1.12 billion on processing plant equipment, $853 million on production purposes, $849 million on exploration activities, $787 million on preparation conducts and $700 million on mining equipment, the ministry noted. Some $1.42 billion were categorized as miscellaneous or "others."

Moreover, existing mining companies in Peru intend to invest another $50 billion this decade in new mines and extension projects, the ministry said, as reported by Dow Jones.

These include a $4 billion expansion project by Sociedad Minera Cerro Verde SAA that will enable it to triple output at its mine located in the Arequipa region.

Minsur SA, Peru's only tin producer, likewise prepares to invest $120 million in the Pucamarca gold mine. Minsur is currently undertaking construction works at the mine, which is expected to be completed in June, with eventual operations to go online in the second half of this year, Dow Jones quoted newspaper El Comercio as saying. The Pucamarca gold mine project is expected to yield 75,000 ounces of gold a year.

A number of top miners can be found in Peru, the world's second biggest producer of copper and silver and a major producer of gold, zinc, lead and other minerals. These include Minera Yanacocha, Xstrata PLC, Minera Chinalco, and Compania Minera Antamina, among others.

According to the Mines and Energy Ministry, Minera Yanacocha invested $1.15 billion in 2011, Xstrata PLC at $763 million, Minera Chinalco at $750 million and Compania Minera Antamina at $640 million.

Majority owned by Newmont Mining Corp., Yanacocha operates South America's largest gold mine and owns the Minas Conga project, Peru's biggest mining development.