UK-based Rio Tinto announced it recently increased its copper mineral resources to 106 million tonnes at its wholly-owned Kennecott Utah Copper Bingham Canyon Mine.

Known as the North Rim Skarn, the addition multiplies the contained metal in mineral resources by 0.73 million tonnes copper, 1.0 million ounces gold and 13 million ounces silver over the 2010 year-end mineral resource estimate.

"While establishing this high grade underground resource at Kennecott Utah Copper is substantial in itself, it points the way to the significant underground potential of the asset," Andrew Harding, chief executive, Rio Tinto Copper said.

The North Rim Skarn is a high-grade copper-gold skarn deposit located approximately 300 metres below the current Bingham Canyon pit.

Rio Tinto has committed US$165 million to complete the next stage of exploration and development studies by 2014. The pre-feasibility programme includes final shaft rehabilitation, an access decline from the pit and further underground exploration drilling. The new investment follows the approval for US$238 million to advance studies extending the open pit life to 2028 as well as the purchase of related long-lead time equipment.

Rio Tinto is a leading international mining group in the UK. It combines Rio Tinto plc, a London and New York Stock Exchange listed company, and Rio Tinto Limited. The latter is listed on the Australian Securities Exchange.

Rio Tinto is engaged in finding, mining, and processing mineral resources. Major products include aluminum, copper, diamonds, thermal and metallurgical coal, uranium, gold, industrial minerals (borax, titanium dioxide and salt) and iron ore. Its' business presence span the world, including Australia and North America, Asia, Europe, Africa and South America.