The mining group is looking to exit its controlling stake in Kumba Iron Ore, Africa's largest producer of the steelmaking ingredient, after the mining group said it will build its future around copper, platinum and diamonds. "We're looking at either a selldown in our position in Kumba as well as a potential demerger," Rene Medori, the chief financial officer of London-based Anglo, which owns a 69.7% stake in Kumba, said on a conference call Tuesday. Anglo "will not expect to complete the transaction until sometime in 2017," Medori said.