Most natural diamonds are 1 to 3 billion years old. They originate deep within the earth's crust and are created under enormous pressure. This makes them the most dense material known to man. They reach the planets surface through volcanoes and most diamonds are found in Kimberlite, a volcanic rock.


Diamonds are made of carbon, the same substance as talc, the softest carbon known. The difference in hardness between the carbons such as talc, gypsum, fluorite and diamonds, for example, is the way the atoms are arranged in the carbon. Diamonds are made under immense pressure so it seems logical that the most pressure the harder the carbon and diamonds are the hardest.

The largest diamond ever found was the Cullinan Diamond in the Premier mine in South Africa in 1905. It weight in at a massive 3,106 carats, or 621.2 grams. This is 6.21 Kilos. It was cut into nine separate stones including the Cullinan or Star of Africa which weights 550.20 carats. This stone is mounted in the British Royal Scepter, part of the British Crown Jewels, and can be found in the Tower of London.

80% of the worlds diamonds are unsuitable for jewelry. They are used in industry for cutting other material or other diamonds and for watches as, for all intents and purposes, cannot wear out.

To get 5 grams of diamond generally requries mining or sorting through about 1 million grams of material but only 20% of these are suitable for jewelry. The rest are used in industry.

Diamonds are thought to be white but in fact can be a range of colors, see Color of Diamonds for more information. Colored diamonds are often called Fancies.