mineral

Diamond (appearing in jewelry)

Diamond (pure Carbon, C)

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

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

Identified April 23, 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 in four directions; Specific Gravity: 3.51

Formation & geological history

Formed deep within the Earth's mantle (150-250km) under extreme pressure and temperature, then brought to the surface by volcanic eruptions of kimberlite or lamproite pipes.

Uses & applications

Primary use in jewelry (gemstones) and industrial applications including cutting, grinding, and drilling tools due to unrivaled 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.

Field identification & locations

Identified in the field by its extreme hardness (cannot be scratched by any other mineral) and its high refractive index (brilliance/fire). This specific piece is a pear-cut faceted gemstone in a halo setting.

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mineral