Diversified industrial trading group Marubeni Corporation  will acquire a 30-per cent stake in leading copper producers Antofagasta Plc to acquire a 30-per cent stake in two of its Esperanza and El Tesoro mining projects for $1.31 billion. Marubeni will also invest $600 million of the estimated $1.9 billion required to develop of the Esperanza project of approximately $0.6 billion, which are currently estimated at approximately  $1.9 billion. Marubeni is therefore, will be investing a total of approximately  $1.9 billion for the Projects.

 The total reserves and resources of the thwo mininng projects are estimated to exceed 1,900 million tonnes. Esperanza is expected to produce 700,000 tonnes of concentrates annually, containing 200,000 tonnes of payable copper. Of this, Marubeni is entitled to sell 210,000 tonnes of concentrates amounting to 5 per cent of Japanese copper imports. El Tesoro currently produces 90,000 tonnes of payable copper each year.

Through this investment, Marubeni expects to secure its markets for Japanese copper imports. Marubeni expects to finance the acquisition from the Japan Bank for International Cooperation and Japan Oil, Gas and Metals National Corporation.

Chile accounts for over one third of the world's copper production and is the largest copper producing country in the world with a number of large-scale copper deposits, a history of successful copper mining, and is recognised as a low-risk country for mining investments. The Esperanza and El Tesoro mining projectsare located in Sierra Gorda in Chile, a key area of focus for Antofagasta.

The area has estimated combined mineral resources of approximately 3 billion tonnes, is an exisiting copper producing area, and its dry climate makes it suitable for mining.   With the planned development of a single mining complex to process both sulphide and oxide ores from the two projects, the area has strong potential for further mining developments. 

The Esperanza project is one of the few high-profile development copper projects remaining globally, and is expected to start the production of copper concentrates, which contains payable copper, by end-2010. Esperanza has proven & probable copper reserves of 480 million tonnes and expected average annual production of 700,000 tonnes of concentrates containing 195,000 tonnes of payable copper, 229,000 ounces of payable gold and 1,556,000 ounces of payable silver over the first ten years. Its operating cost competitiveness is favorable when measured against other copper mining projects currently in development.

 Marubeni is entitled to sell up to 30 per cent of the total concentrates from the Esperanza project, which will account for 5 per cent of total copper imports into Japan This will contribute to securing copper resources for the national interest of Japan. Development of the Telégrafo deposit which is adjacent to Esperanza could extend the life of mine for the Esperanza project up to 2049, beyond the current end of mine life estimate of 2025.

 The El Tesoro copper mine began development in 1999, and commenced production in 2001 using surface mining and the SX-EW process. El Tesoro has already established a solid operating base and a strong track record, with 93,000 tonnes of payable copper produced and EBITDA of US$431 million in FY2007. El Tesoro has proven & probable ore reserves (including the Tesoro North-East project) of 127 million tonnes. Development of Tesoro North-East, a satellite deposit of Tesoro mine could extend the mine life to 2020.

 Marubeni and Antofagasta have agreed to maximize the synergies between the two projects through utilization of the existing El Tesoro infrastructure for the Esperanza project. Furthermore, Marubeni and Antofagasta have agreed on a co-investment scheme for other new development projects in the Sierra Gorda District, with the aim of securing additional copper resources.

 Antofagasta is one of the largest copper producers in the world and the only London Stock Exchange listed company among Chilean copper companies. Marubeni and Antofagasta have been co-operating on the Los Pelambres project in Chile, which is 60 per cent owned by Antofagasta, and have established  a strong relationship. relationship.

 Marubeni's Metals & Mineral Resources division has developed a strategy to secure stable supplies of metal and mineral resources while maximizing profitability through investment in mine developments and smelting projects overseas. This transaction perfectly fits its investment philosophy. Total payable copper from Marubeni's interests is expected to be 120,000 tonnes per year by 2011.