gemstone

Diamond

Natural Diamond (Carbon, C)

Hardness: 10 (Mohs scale), Color: Colorless to faint yellow, Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Perfect octahedral, Specific Gravity: 3.52

Identified July 10, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale), Color: Colorless to faint yellow, Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Perfect octahedral, Specific Gravity: 3.52

Formation & geological history

Formed under extreme pressure and high temperature in the Earth's mantle (150-250km deep), brought to the surface via volcanic pipes called kimberlites. Most are 1-3.5 billion years old.

Uses & applications

Used extensively in jewelry as the primary gemstone for engagement rings; also used in industrial cutting, grinding, and drilling tools due to extreme hardness.

Geological facts

Diamond is the hardest natural substance known on Earth. It is a polymorphic form of carbon and is prized for its high dispersion of light, creating 'fire'.

Field identification & locations

Identified by high refractive index, extreme hardness (scratches all other minerals), and thermal conductivity. Commonly found in alluvial deposits or within kimberlite pipes in regions like Africa, Russia, and Canada.