Xstrata Copper’s 2011 exploration programs at its Las Bambas and Coroccohuayco projects in southern Peru and its El Pachón project in Argentina added significant resources at each project.

At Las Bambas, the mineral resource estimate now totals 1.7 billion mt at a grade of 0.60% copper, using a 0.2% copper cut-off grade, an increase of 10% compared to the previous estimate, dated October 1, 2010. Contained copper metal in the resource has risen by 9% to 10.3 million mt. Measured and indicated resources represent 71% of the total resource. Xstrata Copper will continue exploration and resource definition drilling programs in the district.

Coroccohuayco is an earlier-stage project located 9 km from Xstrata’s Tintaya-Antapaccay operation. The Coroccohuayco deposit is being evaluated as a potential open-pit satellite mine to expand production further at Tintaya-Antapaccay. As a result of 2011 near-surface drilling, the Coroccohuayco project mineral resource has risen by 250% to 324 million mt at a grade of 0.93% copper, using a 0.3% cut-off, and includes significant gold, silver and molybdenum. During 2012, Xstrata Copper plans to conduct a further 40,000 m of drilling and commence prefeasibility studies into Coroccohuayco’s development. This will be undertaken in parallel with a resource expansion program at Antapaccay to significantly expand Antapaccay’s existing mineral resource base of 817 million mt at a copper grade of 0.50%.

At El Pachón, the mineral resource estimate has increased by 53% to a total of 2.7 billion mt at a grade of 0.48% copper using a cut-off grade of 0.2% copper. This represents 13.1 millon mt of contained copper metal, a 44% increase compared to the previous estimate. The new estimate is the result of 56,000 m of infill and step-out drilling that were completed as part of the project’s final feasibility study. (www.xstratacopper.com)