What are diamonds?
Created before life began on our planet, diamonds have always been associated with mystery, myth and magic.
As diamonds require specific geological conditions in order to form, they are only found in certain remote locations around the world.
Southern Africa produces the majority of the world’s diamonds, but there are also diamond productions in Russia, Canada, Australia, India, China and South America.
Based on 2006 Kimberley Process production statistics, Botswana is the world’s biggest producer of diamonds by value, followed by Russia, Canada, South Africa and Angola.
The diamond (from the ancient Greek adámas, meaning "proper" or "unalterable") is one of the best-known and most sought-after gemstones. Diamonds have been known to humankind and used as decorative items since ancient times; some of the earliest references can be traced to India. Diamonds hardness and high dispersion of light make it useful for industrial applications and jewellery.
One of the characteristics of diamonds that make them so desirable as jewellery is their tendency to disperse white light into its component colours, giving the diamond its characteristic "fire". Diamonds are such a highly traded commodity that multiple organizations have been created for grading and certifying diamonds based on the four C's which are carat, cut, colour, and clarity.
A diamond, composed of carbon, is the hardest natural substance in the world. Each carbon atom is surrounded by four neighbouring carbon atoms in a tetrahedral coordination that is the result of a covalent bond and a face-centred arrangement in the cubic unit cell. Diamonds are in the isometric crystal system, which is reflected in the commonly found octahedral or cubic crystal form.
The external crystal class is 4/mBar32/m, while the space group designation is F41dBar32/m. Twins are common on the {111} plane. It has perfect four directional cleavage, adamantine lustre, and both a high refractive index, 2.42, and specific gravity, 3.52. Colour is usually pale yellow to colourless, but can also be brown, blue, green, orange, red, and black.
Diamonds may be up to 3 billion years old, which is much older than their surface host rock (Harlow, 1998, p. 60). Diamond crystallization originates some 200 kilometeres, or 320 miles, beneath the surface and the disaggregated crystals are merely transported to the surface via kimberlite and lamproite pipes (Harlow, 1998, p. 54). These igneous host rock formations are roughly cylindrical in shape and act as a conduit from the Earth's mantle to the continental
crust.
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