Union Minière du Haut-Katanga

Union Minière du Haut-Katanga (UMHK, lit. 'Mining Union of Upper Katanga') was a mining company active in Belgian Congo and especially its Katanga Province. It controlled and operated the mining industry in the copperbelt region, now part of the Democratic Republic of the Congo, between 1906 and 1966.

Created in 1906, the UMHK was founded as a joint venture of the Belgian Compagnie du Katanga, the Belgian Comité Spécial du Katanga and Tanganyika Concessions Limited (TCL, also known as "Tanks"). The Compagnie du Katanga in turn was a subsidiary of the Compagnie du Congo pour le Commerce et l'Industrie (CCCI). With the support of the colonial state, the company was allocated a 7,700 square miles (20,000 km2) concession in Katanga.

Its primary product was copper, but it also produced tin, cobalt, radium, uranium, zinc, cadmium, germanium, manganese, silver, and gold. UMHK was part of a powerful group of global copper producers. By the start of World War II, the Société Générale de Belgique, which controlled about 70 percent of the Congolese economy, exercized preponderant influence over the Comité spécial and effectively controlled the UMHK. 

In 1968, following nationalization of its Congolese mining operations two years earlier, the UMHK reorganized and rebranded itself as Union Minière (UM). UM in 1989 absorbed other entities and in 2001 renamed itself Umicore.