diamond

Definitions

a carbon based stone that is very valuable

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(Noun) a precious, expensive stone.

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(Noun) a rare, hard, valuable stone.

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(Noun) A crystalline stone composed of carbon molecules that is formed under extremely high pressures, usually deep within the earth, or artificially within specially designed machines. It is one of the hardest materials known to man. Diamonds are highly prized gemstones, if they meet certain specifications. They are also valued in industrial settings since they can be used for cutting, drilling, and sanding.

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(Noun) a gem created when coal is put under immense pressure and heat, usually underground