gemstone

Diamond (Faceted)

Diamond (Pure Carbon, C)

Hardness: 10 (Mohs scale); Color: Colorless to faint yellow; Luster: Adamantine; Crystal Structure: Isometric-hexoctahedral; Specific Gravity: 3.51–3.53; Cleavage: Perfect octahedral.

Hardness: 10 (Mohs scale)
Color: Colorless to faint yellow
Luster: Adamantine

Identified July 12, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale); Color: Colorless to faint yellow; Luster: Adamantine; Crystal Structure: Isometric-hexoctahedral; Specific Gravity: 3.51–3.53; Cleavage: Perfect octahedral.

Formation & geological history

Formed under high pressure and temperature conditions deep in the Earth's mantle, then brought to the surface by kimberlite and lamproite pipes.

Uses & applications

Used primarily in fine jewelry (engagement rings, necklaces) and for industrial purposes such as cutting, grinding, and drilling due to extreme hardness.

Geological facts

Diamonds are the hardest known natural substance. The largest gem-quality diamond ever found was the Cullinan Diamond, weighing 3,106 carats before being cut.

Field identification & locations

Identify using a thermal conductivity meter or by looking for high dispersion (fire). Commonly found in South Africa, Russia, Canada, and Botswana. Note: Large, loose faceted stones often require lab certification to verify against synthetics or stimulants.