mineral

Diamond (specifically Blue Diamond color appearance)

Carbon (C) with trace Boron

AI-generated identification · may be incorrect

Hardness: 10 (Mohs), Color: Light blue/grayish-blue, Luster: Adamantine, Crystal Structure: Isometric-hexoctahedral (cubic), Cleavage: Perfect in four directions

Identified June 11, 2026More mineral →

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Physical properties

Hardness: 10 (Mohs), Color: Light blue/grayish-blue, Luster: Adamantine, Crystal Structure: Isometric-hexoctahedral (cubic), Cleavage: Perfect in four directions

Formation & geological history

Formed under extreme pressure and high temperatures deep in the Earth's mantle, approximately 100 to 150 miles below the surface. They are brought to the surface via volcanic eruptions called kimberlite or lamproite pipes.

Uses & applications

Primarily used in high-end jewelry (rings/necklaces) and for industrial cutting, grinding, and drilling due to its unrivaled hardness.

Geological facts

Blue diamonds are among the rarest and most expensive in the world. Their blue color is caused by trace amounts of the element boron trapped within the carbon crystal structure during formation.

Field identification & locations

Identify in the field by high refractive index (brilliance) and hardness test. Found in kimberlite pipes or alluvial deposits. Most famous blue diamonds come from the Cullinan mine in South Africa.