gemstone

Diamond

Diamond (C)

Hardness: 10 on the Mohs scale; Color: Colorless to near-colorless; Luster: Adamantine; Crystal System: Isometric/Cubic; Specific Gravity: 3.52; Cleavage: Perfect octahedral {111}

Hardness: 10 on the Mohs scale
Color: Colorless to near-colorless
Luster: Adamantine

Identified July 24, 2026More gemstone →

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Physical properties

Hardness: 10 on the Mohs scale; Color: Colorless to near-colorless; Luster: Adamantine; Crystal System: Isometric/Cubic; Specific Gravity: 3.52; Cleavage: Perfect octahedral {111}

Formation & geological history

Formed under extreme pressure and temperature conditions deep within the Earth's mantle (150-200 km down), brought to the surface via deep-origin volcanic eruptions (kimberlite and lamproite pipes).

Uses & applications

Widely used in fine jewelry (engagement rings, gemstone settings) and in industrial applications like cutting tools, drill bits, abrasives, and high-tech optics due to extreme hardness.

Geological facts

Diamond is the hardest known natural substance. It consists of pure carbon atoms arranged in a strong 3D crystal lattice. While natural diamonds are billions of years old, synthetic cubic zirconia or moissanite are common lookalikes.

Field identification & locations

Identified by incredible hardness, adamantine brilliance, high dispersion (fire), and thermal conductivity. Tested with thermal/electrical diamond testers or refractometers. Common sources include Russia, Botswana, Canada, and South Africa.