mineral

Diamond (in jewelry)

Element Carbon (C)

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Isometric (cubic), Cleavage: Perfect in four directions, Specific Gravity: 3.52

Identified June 23, 2026More mineral →

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Physical properties

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Isometric (cubic), Cleavage: Perfect in four directions, Specific Gravity: 3.52

Formation & geological history

Formed under extreme high pressure and temperature in Earth's mantle, approximately 100 miles below the surface, and brought to the surface by kimberlite eruptions. Ages range from 1 to 3.5 billion years.

Uses & applications

Primary use in fine jewelry as gemstones; industrial uses include cutting, grinding, and drilling tools due to extreme hardness.

Geological facts

Diamonds are the hardest known natural substance on Earth. Most natural diamonds are billions of years old, predating dinosaurs by hundreds of millions of years.

Field identification & locations

Identification includes testing for high thermal conductivity and viewing the 'marquise' cut facets. Natural specimens are found in kimberlite pipes or alluvial deposits.