gemstone

Diamond

Carbon (C)

Hardness: 10 (Mohs scale); Color: Colorless (in this specimen); Luster: Adamantine; Crystal Structure: Isometric-hexoctahedral; Cleavage: Perfect in four directions; Specific Gravity: 3.5–3.53

Hardness: 10 (Mohs scale)
Color: Colorless (in this specimen)
Luster: Adamantine

Identified July 16, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale); Color: Colorless (in this specimen); Luster: Adamantine; Crystal Structure: Isometric-hexoctahedral; Cleavage: Perfect in four directions; Specific Gravity: 3.5–3.53

Formation & geological history

Formed under high-pressure, high-temperature conditions deep within the Earth's mantle (usually 140–190 km deep). They are brought to the surface by rare kimberlite or lamproite volcanic eruptions. Most natural diamonds are between 1 billion and 3.5 billion years old.

Uses & applications

Primarily used in high-end jewelry (engagement rings, necklaces), and industrial applications for cutting, drilling, and grinding due to its extreme hardness.

Geological facts

The word diamond comes from the Greek word adamas, meaning invincible. They are the only gemstone made of a single element: Carbon. Famous specimens include the Hope Diamond and the Cullinan Diamond.

Field identification & locations

Identify by its brilliance, fire (dispersion of light), and inability to be scratched by any other material. Commonly found in secondary alluvial deposits or primary kimberlite pipes in Africa, Russia, Canada, and Australia.