In which country does the prominent geological feature, "the Great Dyke", occur?

The Great Dyke is a prominent igneous intrusion running for a distance of over 500km, down the centre of Zimbabwe. It is a layered structure, consisting mainly of serpentinite and pyroxenite rocks. Strictly speaking, in geological terms, it consists of four linear lopoliths and the feature is dated at some 2,500Ma (2,500 million years old).

The Great Dyke contains significant deposits of chromite and Zimbabwe is a major producer of ferrochrome. During the UDI era, prior to the country's political change to become Zimbabwe, its ferrochrome was considered of such importance that the US government exempted the commodity from economic sanctions against Rhodesia. The chromite occurs in very narrow seams, typically only 100 - 200mm thick, and is extracted in underground mines by very labour-intensive methods, often by small-scale miners working in co-operatives supplying large companies with ore.

The Great Dyke is also host to platinum-group metals, containing the second-largest known resources in the world after South Africa, and Zimbabwe is an important producer of platinum and associated minerals.