gemstone

Diamond

Carbon (C)

Hardness: 10 on the Mohs scale. Color: Colorless to faint yellow/brown (can be fancy colors). Luster: Adamantine. Crystal Structure: Isometric-hexoctahedral (cubic). Specific Gravity: 3.52. Perfect octahedral cleavage.

Hardness: 10 on the Mohs scale
Color: Colorless to faint yellow/brown (can be fancy colors)
Luster: Adamantine

Identified July 26, 2026More gemstone →

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Physical properties

Formation & geological history

Forms deep within Earth's mantle (100 to 150 miles underground) under extreme pressure and high temperatures over billions of years, brought to the surface via deep-source volcanic eruptions (kimberlite pipes).

Uses & applications

Widely set in high-end fine jewelry (rings, necklaces, bands). Also heavily used in industrial applications for cutting, grinding, drilling, and polishing due to extreme hardness.

Geological facts

Diamond is the hardest naturally occurring substance on Earth. It consists of pure carbon atoms arranged in a rigid tetrahedral lattice structure.

Field identification & locations

Identified by incredible hardness, adamantine brilliance, and thermal conductivity. Commonly set in precious metals like gold or platinum for engagement rings.