The Bushveld Igneous Complex (BIC) is the largest layered igneous intrusion within the Earth's crust. It has been tilted and eroded forming the outcrops around what appears to be the edge of a great geological basin: the Transvaal Basin. It is approximately two billion years old and is divided into four limbs or lobes: northern, eastern, southern and western. It comprises the Rustenburg Layered suite, the Lebowa Granites and the Rooiberg Felsics, that are overlain by the Karoo sediments. The site was first publicised around 1897 by Gustaaf Molengraaff who found the native South African tribes residing in and around the area.
Located in South Africa, the BIC contains some of the richest ore deposits on Earth. It contains the world's largest reserves of platinum-group metals (PGMs) and platinum group elements (PGEs) — platinum, palladium, osmium, iridium, rhodium and ruthenium — along with vast quantities of iron, tin, chromium, titanium and vanadium. These are used in, but not limited to, jewellery, automobiles and electronics. Gabbro or norite is also quarried from parts of the complex and rendered into dimension stone. There have been more than 20 mine operations. There have been studies of potential uranium deposits. The complex is well known for its chromitite reef deposits, particularly the Merensky reef and the UG2 reef. It represents about 75 percent of the world's platinum and about 50 percent of the world's palladium resources. In this respect, the Bushveld complex is unique and one of the most economically significant mineral deposit complexes in the world.
