gemstone

Diamond

C (Native Carbon)

Hardness: 10 on Mohs scale. Color: Colorless (clear) to near-colorless with brilliant fire/dispersion. Luster: Adamantine. Crystal System: Cubic (Isometric). Specific Gravity: 3.52.

Hardness: 10 on Mohs scale
Luster: Adamantine

Identified July 26, 2026More gemstone →

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Physical properties

Hardness: 10 on Mohs scale. Color: Colorless (clear) to near-colorless with brilliant fire/dispersion. Luster: Adamantine. Crystal System: Cubic (Isometric). Specific Gravity: 3.52.

Formation & geological history

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

Uses & applications

Extensively used in fine jewelry (engagement rings, necklaces, earrings) as well as heavy industrial applications like cutting, drilling, grinding, and polishing tools due to its unparalleled hardness.

Geological facts

Diamond is the hardest naturally occurring substance on Earth, made entirely of pure carbon atoms arranged in a strong crystal lattice. It is also the April birthstone and the traditional gift for 60th wedding anniversaries.

Field identification & locations

Identified by its incredible hardness (scratches all other minerals), intense adamantine luster, high refractive index, and thermal conductivity. Found in volcanic kimberlite pipes or alluvial placer deposits in Russia, Botswana, Canada, Australia, and South Africa.