gemstone

Diamond

Carbon (C)

Hardness: 10 on Mohs scale (hardest known natural substance). Color: Colorless (white), yellow, brown, blue, green, pink, red, black. Luster: Adamantine (exceptionally brilliant and sparkly). Crystal structure: Isometric (cubic). Specific gravity: 3.50-3.53.

Hardness: 10 on Mohs scale (hardest known natural substance)
Luster: Adamantine (exceptionally brilliant and sparkly)

Identified July 28, 2026More gemstone →

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Physical properties

Formation & geological history

Formed deep within the Earth's mantle (about 100-150 miles down) under extreme high pressure and temperature conditions, then brought closer to the surface via deep-source volcanic eruptions (kimberlite and lamproite pipes) over hundreds of millions to billions of years.

Uses & applications

Extensively used as a precious gemstone in fine jewelry, engagement rings, and high-end watches. Due to its extreme hardness and thermal conductivity, industrial-grade diamonds are widely used in cutting, grinding, drilling tools, and heat sinks.

Geological facts

Diamond is the only gemstone composed of a single element (pure carbon). Despite sharing the exact same chemical composition as soft graphite, its tight, three-dimensional covalent bonding gives it incomparable hardness.

Field identification & locations

Can be identified by its exceptional brilliance, fire (dispersion of light into spectral colors), adamantine luster, and ability to scratch all other minerals. Found globally in major deposits across Africa (e.g., South Africa, Botswana), Russia, Canada, and Australia.