Carbon the very large masses of carbonate rock (limestone, dolomite, marble and so on). Coal is very rich in carbon (anthracite contains 92–98%) and is the largest commercial source of mineral carbon, accounting for 4,000 gigatonnes or 80% of fossil fuel. As for individual carbon allotropes, graphite is found in large quantities in the United States (mostly in New York and Texas), Russia, Mexico, Greenland, and India. Natural diamonds occur in the rock kimberlite, found in ancient volcanic "necks", or "pipes". Most diamond deposits are in Africa, notably in South Africa, Namibia, Botswana, the Republic of the Congo, and Sierra Leone.
Coal pollution mitigation to encourage the introduction of coal pollution mitigation and other technologies to reduce environmental impact. Combustion of coal--which is mostly carbon--produces carbon dioxide as a product of combustion. According to the United Nations Intergovernmental Panel on Climate Change, the burning of coal, a fossil fuel, is a significant contributor to global warming. (See the UN IPCC Fourth Assessment Report). For 1 ton of coal burned, 2.86 tons of carbon dioxide is created. Carbon sequestration technology has yet to be tested on a large scale and may not be safe or successful. Sequestered CO may eventually leak up through the ground,