gemstone

Diamond

Carbon (C)

Hardness: 10 (Mohs scale), Color: Colorless to faint yellow/brown, Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Perfect octagonal, Specific Gravity: 3.5-3.53

Identified July 6, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale), Color: Colorless to faint yellow/brown, Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Perfect octagonal, Specific Gravity: 3.5-3.53

Formation & geological history

Formed under intense heat and pressure deep within the Earth's mantle, approximately 100 miles below the surface, usually between 1 to 3 billion years ago. They are brought to the surface by kimberlite and lamproite pipes.

Uses & applications

Primarily used in jewelry; also widely used in industrial applications such as cutting, grinding, and drilling due to its extreme hardness.

Geological facts

Diamond is the only gemstone made of a single element (carbon). It is the hardest natural substance known to man. The famous Hope Diamond is known for its rare blue color and alleged curse.

Field identification & locations

Identify by its brilliance, extreme hardness (scratches all other materials), and thermal conductivity. Commonly found in South Africa, Russia, Canada, and Botswana. Collectors should verify authenticity with a diamond tester or GIA certification.