mineral

Diamond (as set in a metal alloy ring)

Diamond (Pure Carbon, C)

Hardness: 10 on Mohs scale (hardest known natural material); Color: colorless to faint yellow (in this specimen); Luster: Adamantine; Crystal structure: Isometric-Hexoctahedral; Specific Gravity: 3.52.

Hardness: 10 on Mohs scale (hardest known natural material)
Color: colorless to faint yellow (in this specimen)
Luster: Adamantine

Identified March 8, 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, usually between 1 to 3.5 billion years ago. They are brought to the surface through deep-origin volcanic eruptions known as kimberlite or lamproite pipes.

Uses & applications

Primary use in high-end jewelry (engagement rings, necklaces); also used industrially for cutting, grinding, and drilling tools due to extreme hardness.

Geological facts

Diamonds are the only gemstone made of a single element: Carbon. They are famous for their 'fire' or dispersion—the ability to split white light into a rainbow of colors. The Cullinan Diamond is the largest gem-quality rough diamond ever found.

Field identification & locations

In the field, raw diamonds are often found as octahedral (eight-sided) crystals in kimberlite host rock. Collectors look for clarity and 'trigon' growth marks on crystal faces. Common locations include South Africa, Russia, Canada, and Botswana.

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