| Carbon is the fourth most abundant chemical element in the universe by mass, after hydrogen, helium, and oxygen. Carbon is abundant in the Sun, stars, comets, and in the atmospheres of most planets. Some meteorites contain microscopic
diamonds that were formed when the solar system was still a protoplanetary disk. In combination with other elements, carbon
is found in the Earth's atmosphere (around 810 gigatonnes) and dissolved in all water bodies (around 36000 gigatonnes). Around
1900 gigatonnes are present in the biosphere. Hydrocarbons (such as coal, petroleum, and natural gas) contain carbon as well
- coal "resources" amount to around 1000 gigatonnes, and oil reserves around 150 gigatonnes. With smaller amounts of calcium, magnesium, and iron, carbon is a major component of very large masses carbonate rock (limestone, dolomite (CaMg(CO3)2), marble etc.).
|
| Natural diamonds occur in the mineral 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. There are also deposits in Arkansas, Canada, the Russian Arctic, Brazil and in Northern and Western Australia.
|
Occurrence