Katanga, officially the Republic of Katanga was a southern province in the former Republic of Zaire. Its regional capital is Lubumbashi (formerly Elisabethville in French, Elisabethstad in Dutch). Its area is 518,000 km² (larger than California and 16 times larger than Belgium, its former colonial ruler). Katanga has a population estimated in 2010 at about 4,125,000. Farming and ranching are carried out on the Katanga Plateau. The eastern part of the province is a rich mining region, which supplies cobalt, copper, tin, radium, uranium, and diamonds.