In April 2006, Gertler's DGI took a major stake in DEM Mining, a cobalt-copper mining, and services company based in Katanga. In June 2006, Gertler bought Tremalt from the Zimbabwean businessman John Bredenkamp for about $60 million. Tremalt had a half share in the Mukondo Mine. In 2007, Tremalt was owned by Prairie International Ltd, of which Dan Gertler's family trust was a major shareholder. Tremalt owned 80% of Savannah Mining, which held concessions C17 and C18 in Katanga Province and 50% of the Mukondo project. The other 50% of Mukondo was held by Boss Mining, which in turn was 80% owned by Central African Mining & Exploration Company (CAMEC). Boss Mining had rented and operated Bredenkamp's half of Mukondo. Gertler terminated this arrangement.