gemstone

Diamond

C (Native Carbon)

Hardness: 10 on Mohs scale. Color: Colorless, white, or light yellow/brown shades (fancy colors also exist). Luster: Adamantine. Crystal Structure: Isometric/Cubic. Cleavage: Perfect in four directions (octahedral). Specific Gravity: 3.52.

Hardness: 10 on Mohs scale
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 (100 to 150 miles down) billions of years ago, then brought close to the surface via volcanic eruptions in kimberlite pipes.

Uses & applications

Primary use is in fine jewelry such as engagement rings, wedding bands, and eternity rings. Also widely used in industrial applications for cutting, drilling, grinding, and polishing due to its unparalleled hardness.

Geological facts

Diamond is the hardest naturally occurring substance known on Earth. It is composed of pure carbon atoms arranged in a rigid crystal lattice.

Field identification & locations

Identified by extreme hardness, high dispersion (fire), brilliance, and thermal conductivity. Commonly mined in Russia, Botswana, Canada, Australia, and South Africa.