gemstone

Diamond

Carbon (C)

Hardness: 10 on Mohs scale; Color: Colorless, yellow, brown, blue, pink; Luster: Adamantine; Crystal structure: Isometric (cubic); Cleavage: Perfect in four directions; Specific gravity: 3.50-3.53

Hardness: 10 on Mohs scale
Color: Colorless, yellow, brown, blue, pink
Luster: Adamantine

Identified August 2, 2026More gemstone →

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Physical properties

Hardness: 10 on Mohs scale; Color: Colorless, yellow, brown, blue, pink; Luster: Adamantine; Crystal structure: Isometric (cubic); Cleavage: Perfect in four directions; Specific gravity: 3.50-3.53

Formation & geological history

Formed under high-pressure and high-temperature conditions (approx. 900-1300 degrees Celsius and 45-60 kilobars) in the Earth's mantle, typically 150-200 kilometers deep, brought to the surface via deep-source volcanic eruptions (kimberlite and lamproite pipes). Geological ages range from 1 billion to over 3 billion years old.

Uses & applications

Widely used in jewelry (engagement rings, necklaces), high-end timepieces, and industrial applications such as cutting, grinding, and drilling tools due to its extreme hardness.

Geological facts

Diamond is the hardest known natural material on Earth. Despite its toughness, it can be split along its cleavage planes with a single well-placed blow.

Field identification & locations

Identified by its adamantine luster, extreme hardness (scratches all other minerals), and high thermal conductivity. Mined primarily in Russia, Botswana, Canada, and South Africa.