mineral

Diamond (in a jewelry setting)

Cubic Carbon (C)

Hardness: 10 Mohs (hardest known natural substance). Color: Colorless (in this specimen). Luster: Adamantine. Crystal Structure: Isometric-hexoctahedral. Cleavage: Perfect in four directions. Specific gravity: 3.52.

Hardness: 10 Mohs (hardest known natural substance)
Color: Colorless (in this specimen)
Luster: Adamantine

Identified March 29, 2026More mineral →

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Physical properties

Formation & geological history

Formed under extreme pressure and temperature conditions in the Earth's mantle, approximately 100 miles below the surface. They are brought to the surface by deep-origin volcanic eruptions called kimberlite pipes. Most geological specimens are 1 to 3.5 billion years old.

Uses & applications

Primary use in fine jewelry (engagement rings, bracelets). Industrially used for cutting, drilling, and grinding tools due to extreme hardness. High thermal conductivity used in semiconductor manufacturing.

Geological facts

Diamonds are the only gemstone made of a single element: Carbon. The word diamond comes from the Greek word 'adamas', meaning unbreakable. They are the birthstone for April.

Field identification & locations

In the field, they are identified by their high refractive index, extreme hardness (will scratch all other minerals), and octahedral crystal habit. Commonly found in alluvial deposits or kimberlite pipes in South Africa, Russia, Canada, and Botswana.