gemstone

Diamond

C (Pure Carbon)

Hardness: 10 on Mohs scale (hardest known natural substance). Color: Colorless/transparent with high dispersion (fire). Luster: Adamantine. Crystal Structure: Isometric-Hexoctahedral (cubic). Specific Gravity: 3.52.

Hardness: 10 on Mohs scale (hardest known natural substance)
Color: Colorless/transparent with high dispersion (fire)
Luster: Adamantine

Identified July 26, 2026More gemstone →

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Physical properties

Formation & geological history

Formed at extreme depths (150-200 km) in Earth's mantle under high pressure and temperature over billions of years, brought to the surface via kimberlite and lamproite volcanic pipes.

Uses & applications

Widely used in fine jewelry (engagement rings, necklaces), as well as industrial applications including cutting tools, drill bits, abrasives, and high-precision optics.

Geological facts

Diamond is the only gemstone made of a single element (carbon). Despite its extreme hardness, it can shatter if struck along its cleavage planes with enough force.

Field identification & locations

Identified by extreme hardness, ability to scratch glass and corundum, high refractive index, and adamantine brilliance. Major sources include Russia, Botswana, Canada, Australia, and South Africa.