gemstone

Diamond

Diamond (Pure Carbon crystallization)

Hardness: 10 (Mohs scale), Color: Clear/Colorless, Luster: Adamantine, Crystal Structure: Isometric-Cubic, Cleavage: Perfect in four directions.

Identified July 6, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale), Color: Clear/Colorless, Luster: Adamantine, Crystal Structure: Isometric-Cubic, Cleavage: Perfect in four directions.

Formation & geological history

Formed under extreme pressure and high temperature in Earth's mantle, approximately 100 miles below the surface, and brought upward by kimberlite pipe volcanic eruptions.

Uses & applications

Primary use in jewelry and high-end luxury goods; also used in industrial cutting, grinding, and drilling tools due to its extreme hardness.

Geological facts

Diamonds are the hardest natural substance on Earth. Most natural diamonds are between 1 billion and 3.5 billion years old.

Field identification & locations

Identified by its high refractive index and hardness. In the field, it is typically found in kimberlite pipes or alluvial deposits. Collectors look for the 'Four Cs': Cut, Color, Clarity, and Carat weight.