gemstone

Diamond

Carbon (C)

Hardness: 10 on the Mohs scale, Color: Colorless to yellow, brown, blue, pink, etc., Luster: Adamantine, Crystal Structure: Isometric (cubic), Cleavage: Perfect octahedral cleavage, Specific Gravity: 3.50-3.53

Color: Colorless to yellow, brown, blue, pink, etc

Identified July 28, 2026More gemstone →

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Physical properties

Formation & geological history

Formed under high-pressure and high-temperature conditions (approx. 900-1300 degrees Celsius and 45-60 kilobars) in the Earth's mantle, typically at depths of 150-200 kilometers, and brought to the surface via deep-source volcanic eruptions (kimberlites and lamproites) mostly during the Precambrian to Cretaceous periods.

Uses & applications

Widely used in high-end jewelry (engagement rings, necklaces), as well as in industrial applications such as cutting, grinding, and drilling tools due to its extreme hardness.

Geological facts

Diamond is the hardest naturally occurring substance on Earth. Famous large diamonds include the Cullinan Diamond, the largest gem-quality diamond ever found.

Field identification & locations

Identified by its supreme hardness (scratching all other minerals), high dispersion (fire), and adamantine luster. Commonly mined in Russia, Botswana, Canada, and South Africa.