mineral

Rough Diamond (Bort)

Diamond (C)

Mohs hardness: 10. Color: Light grey to brownish-grey. Luster: Adamantine to greasy/dull in rough form. Crystal system: Isometric/Cubic. Cleavage: Perfect octahedral in four directions. Specific gravity: 3.51-3.53.

Hardness: 10
Color: Light grey to brownish-grey
Luster: Adamantine to greasy/dull in rough form

Identified July 24, 2026More mineral →

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Physical properties

Formation & geological history

Formed under extreme pressure and temperature conditions deep within the Earth's mantle (150-200 km below the surface) billions of years ago, brought to the surface via explosive kimberlite and lamproite pipe eruptions.

Uses & applications

Rough industrial diamonds (bort) are widely used as abrasives, cutting and drilling tools, polishing powders, and in specialized optical windows or scientific instruments.

Geological facts

Diamond is a native element mineral composed of pure carbon arranged in a tetrahedral crystal structure. It is the hardest known naturally occurring mineral on Earth.

Field identification & locations

Identified by its extreme hardness (scratches all other minerals), greasy to sparkly adamantine luster, octahedral or irregular rough growth habits, and high thermal conductivity. Found in kimberlite pipes and alluvial deposits in Russia, Botswana, Canada, Australia, and South Africa.