AngloGold Ashanti increased gold reserves at the Tropicana project in Western Australia to 3.91 million oz as of the end of June 2011, up from 3.37 million oz at year-end 2010. Project resources have also increased, up from 5.28 million oz to 5.36 million oz.
Tropicana is a joint-venture project located 330 km east-northeast of Kalgoorlie, Western Australia. Ownership is AngloGold Ashanti Australia (70% and manager) and Independence Group (30%). The project was approved for development in November 2010.
Project planning at Tropicana is based on five deposits stretched across a distance of 4 km: Havana South open cut, Havana open cut, Havana Deeps underground, Tropicana open cut and Boston Shaker open cut. The new reserve and resource estimates primarily reflect increased drill density in the Havana South and Boston Shaker zones, as well as increased gold prices and changes in the resource model.
Drilling is continuing in the Swizzler area, between the Tropicana and Havana open cuts, and at Havana Deeps. A pre-feasibility study is being carried out on open-pit and underground mining options for the Havana Deeps mineralization.
Tropicana development, based on reserves as of November 2010, calls for production of 470,000–490,000 oz/y of gold during the first three years of production and an average of 330,000–350,000 oz/y over a mine life of at least 10 years. Cash costs are forecast at A$580/oz to A$600/oz during the first three years of production, and capital costs are estimated at A$690–A$740 million. The project remains on schedule to pour its first gold in late 2013.