gemstone

Diamond

Carbon (C)

Hardness: 10 on the Mohs scale, Color: Colorless, yellow, brown, blue, pink, green, Luster: Adamantine, Crystal Structure: Isometric (cubic), Cleavage: Perfect octahedral cleavage, Specific Gravity: 3.50-3.53

Identified August 1, 2026More gemstone →

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Physical properties

Formation & geological history

Formed under high pressure and temperature conditions in Earth's mantle, typically at depths of 150 to 250 kilometers, and brought to the surface through deep-seated volcanic eruptions of kimberlite or lamproite magmas, with ages ranging from 1 to over 3 billion years.

Uses & applications

Widely used in fine jewelry and engagement rings due to its exceptional brilliance and fire; extensively used in industrial applications including cutting, grinding, drilling, and polishing tools due to its extreme hardness.

Geological facts

Diamond is the hardest known natural material on Earth, yet it is made entirely of carbon, the same element that forms soft graphite in pencils. Some colored diamonds, known as fancy diamonds, get their rare hues from natural radiation or atomic lattice defects.

Field identification & locations

Identified by its supreme hardness, high refractive index, and adamantine luster. Commonly found in major deposits in South Africa, Russia, Canada, Australia, and Botswana. Collectors look for clarity, cut, color, and carat weight.