Carbonado
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Carbonado, commonly known as black diamond, is one of the toughest forms of natural diamond. It is an impure, high-density, micro-porous form of polycrystalline diamond consisting of diamond, graphite, and amorphous carbon, with minor crystalline... Wikipedia
Category: Native minerals
Color: Typically black, can be grey, various shades of green and brown sometimes mottled
Crystal habit: Polycrystalline
Crystal system: Isometric-hexoctahedral (cubic)
Density: 3.5–3.53 g/cm3
Formula mass: 12.01 u
Formula (repeating unit): C