mineral

Diamond

Native Carbon (C)

Hardness: 10 (Mohs scale); Color: Colorless (purest), yellow, brown, or blue; Luster: Adamantine; Crystal Structure: Isometric (cubic); Cleavage: Perfect in four directions (octahedral); Specific Gravity: 3.52

Hardness: 10 (Mohs scale)
Color: Colorless (purest), yellow, brown, or blue
Luster: Adamantine

Identified March 15, 2026More mineral →

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Physical properties

Formation & geological history

Formed deep in the Earth's mantle (150-250 km deep) under extreme high pressure and temperature; delivered to the surface via deep-source volcanic eruptions called kimberlite or lamproite pipes, often billions of years old.

Uses & applications

Primary use in jewelry as gemstones; industrial uses include cutting, grinding, and drilling tools due to extreme hardness; used in high-pressure scientific experiments (diamond anvil cells).

Geological facts

Diamond is the hardest natural substance known to man. It is a polymorph of coal and graphite, meaning it is made of the same element (carbon) but arranged in a different crystal structure. The Cullinan Diamond is the largest gem-quality rough diamond ever found.

Field identification & locations

Identify by its ability to scratch all other minerals, high thermal conductivity, and adamantine luster. Found in placer deposits in rivers or in primary kimberlite pipes. Collectors look for 'Herks' (quartz) often as mimics, but true diamonds are cold to the touch and exhibit high dispersion.