mineral

Diamond (faceted)

Diamond (Pure Carbon, C)

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Isometric-Hexoctahedral, Cleavage: Perfect octahedral, Specific Gravity: 3.51

Identified May 30, 2026More mineral →

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Physical properties

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Isometric-Hexoctahedral, Cleavage: Perfect octahedral, Specific Gravity: 3.51

Formation & geological history

Formed under high-pressure, high-temperature conditions in Earth's mantle, approximately 100 miles underground, and transported to the surface via kimberlite or lamproite volcanic eruptions. Most are 1 to 3.5 billion years old.

Uses & applications

Commonly used in fine jewelry (engagement rings, necklaces), and industrially for cutting, drilling, and grinding tools due to its extreme hardness.

Geological facts

Diamond is the hardest known natural substance. The word comes from the Greek 'adamas', meaning unbreakable. They are the only gemstone made of a single element.

Field identification & locations

Identify by its brilliance, ability to scratch sapphire, and thermal conductivity. Found in primary deposits (kimberlite pipes) or secondary alluvial deposits in rivers and beaches, notably in Africa, Russia, Canada, and Australia.