gemstone

Diamond

Carbon (C)

Hardness: 10 (Mohs scale), Color: Clear/Colorless (most common for jewelry), Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Perfect octahedral, Specific Gravity: 3.51

Identified July 11, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale), Color: Clear/Colorless (most common for jewelry), Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Perfect octahedral, Specific Gravity: 3.51

Formation & geological history

Formed deep within the Earth's mantle (about 100 miles down) under intense heat (2,200°F) and extreme pressure (725,000 psi). Most are 1 to 3.5 billion years old.

Uses & applications

Fine jewelry (engagement rings, bracelets), industrial cutting tools, abrasives, and high-performance heat sinks in electronics.

Geological facts

Diamonds are the hardest natural substance on Earth. They are brought to the surface through deep-source volcanic eruptions known as kimberlite pipes. The name comes from 'adamas', meaning unbreakable.

Field identification & locations

Identified by superior hardness, refractive index, and thermal conductivity. Found primarily in Russia, Botswana, Canada, and South Africa. Collectors should look for the 'Four Cs': Cut, Clarity, Color, and Carat weight.