GREAT DYKE

narrow series of long, low ridges and hills in Zimbabwe, trending for about 320 miles (515 km). Consisting of four igneous complexes, they increase in height northward to about 1,500 feet (460 m) above the plateau surface in the Umvukwe Range, west of Harare (formerly Salisbury), the Zimbabwean capital. Minerals found in the Great Dyke include gold, silver, chromium, platinum, and nickel. Mica, asbestos, and tin are also extracted, as are minerals useful in construction.