gemstone

Diamond

Carbon (C)

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Octahedral, Specific Gravity: 3.51-3.53

Identified July 6, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Octahedral, Specific Gravity: 3.51-3.53

Formation & geological history

Formed at high temperatures and pressures at depths of 140 to 190 kilometers in the Earth's mantle over periods of 1 billion to 3.3 billion years. Brought to the surface through deep-source volcanic eruptions called kimberlite pipes.

Uses & applications

Primarily used in high-end jewelry and as an industrial abrasive for cutting, drilling, and grinding due to its unmatched hardness.

Geological facts

Diamond is the hardest natural material known to man. It is a crystalline form of pure carbon. The word diamond is derived from the Greek 'adamas', meaning unbreakable.

Field identification & locations

Identify by its exceptional brilliance, fire, and ability to scratch any other material. Commonly found in South Africa, Russia, Canada, and Botswana. For faceted stones, check for sharpness of facet junctions and lack of wear.