Northern Rhodesia the British South Africa Company administered territory of North-Western Rhodesia (now in Zambia), and Portuguese Angola although its boundary with Angola was not marked-out on the ground until later. The northern border of the British territory in North-Eastern Rhodesia and the British Central Africa Protectorate was agreed as part of an Anglo-German Convention in 1890, which also fixed the very short boundary between North-Western Rhodesia and German South-West Africa, now Namibia. The boundary between the Congo Free State and British territory was fixed by a treaty in 1894, although there were some minor adjustments up to the 1930s. Boundaries with
Northern Rhodesia these copper deposits could not be exploited commercially until the Southern Rhodesian railway had extended across the Zambezi and continued northward, to reach the Belgian Congo border, which it did in 1909. By that time, mining had started in Katanga, where rich copper oxide ores occurred near the surface. In Northern Rhodesia, the surface ores were of poorer quality, and copper was only worked intermittently at Bwana Mkubwa, until in 1924 rich copper sulphide ores were discovered about 100 feet below the surface. Prior to 1924, there had not been significant exploitation of Northern Rhodesia's mineral resources: there was some