:: Xstrata Technology’s Isa Process^® Selected for the Piedras Verdes Project in Mexico

Xstrata Technology is pleased to announce that Frontera Copper Corporation has recently selected Xstrata’s ISA PROCESS^® electrowinning technology for its Piedras Verdes run of mine heap leach / SXEW copper project in the state of Sonora, Mexico. Piedras Verdes is owned and operated by Cobre del Mayo, S.A. de C.V., a wholly owned subsidiary of Frontera Copper. The production capacity of the electrowinning plant will be 70 million pounds per year of LME Grade A quality copper cathode. The plant is currently in the design and procurement phase of development.

The ISA PROCESS^® supply includes the ISA Cathode BR^®, and technology transfer services, integrated with the Cathode Washing and Stripping Machine to complete the ISA PROCESS^® package of core tankhouse design & equipment. The BR cathode was chosen as the lowest resistance cathode on the market designed for low energy consumption and high efficiency throughout a long operating life. The stripping machine will be manufactured by MESCO Inc. of Japan, which has had a long association with the ISA PROCESS since its development in the late 1970s. ISA PROCESS Manager John Doolan said, "We are very pleased to be working with Frontera Copper on this project. We have worked together to deliver technical design oversight, equipment and commissioning assistance for the tankhouse. We look forward to Piedras Verdes producing the highest quality cathode, as with all ISA PROCESS^® plants. The project is scheduled for completion in mid 2006. This rapid development time table is a challenge that the ISA PROCESS^® team is ready to meet."

The Piedras Verdes Project becomes the latest user of the proven ISA PROCESS^® copper electrowinning system - when operational, it will mean ISA PROCESS^® installations total more than 60 worldwide, including world leading electrowinning and electrorefining facilities in over 21 countries.