gemstone

Diamond

Native Carbon (C)

Hardness: 10 on the Mohs scale (hardest known natural substance). Color: Colorless/near-colorless. Luster: Adamantine. Crystal Structure: Isometric (cubic). Specific Gravity: 3.52. High dispersion and brilliance.

Hardness: 10 on the Mohs scale (hardest known natural substance)
Color: Colorless/near-colorless
Luster: Adamantine

Identified July 23, 2026More gemstone →

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Physical properties

Formation & geological history

Formed under extreme pressure and high temperatures deep within Earth's mantle (about 90-120 miles down) over billions of years, brought to the surface via deep-source volcanic eruptions in kimberlite and lamproite pipes.

Uses & applications

Set in fine jewelry such as eternity bands and engagement rings; also widely used in industrial applications for cutting, drilling, and grinding due to its hardness.

Geological facts

Diamond is a solid form of pure carbon with its atoms arranged in a crystal structure called diamond cubic. It holds the highest thermal conductivity of any natural material.

Field identification & locations

Identified by incredible hardness (scratches all other minerals), high refractive index, and brilliance. Commonly mined in Russia, Botswana, Canada, and Australia.