gemstone

Diamond

Natural Diamond (Carbon, C)

Hardness: 10 Mohs; Color: Colorless to faint yellow/brown; Luster: Adamantine; Crystal Structure: Isometric (cubic); Cleavage: Perfect octahedral; Specific Gravity: 3.52

Hardness: 10 Mohs
Color: Colorless to faint yellow/brown
Luster: Adamantine

Identified July 6, 2026More gemstone →

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Physical properties

Hardness: 10 Mohs; Color: Colorless to faint yellow/brown; Luster: Adamantine; Crystal Structure: Isometric (cubic); Cleavage: Perfect octahedral; Specific Gravity: 3.52

Formation & geological history

Formed under high temperature and pressure conditions in the Earth's mantle (100-150 miles deep) billions of years ago. Transported to the surface by deep-source volcanic eruptions (kimberlite or lamproite pipes).

Uses & applications

Primarily used in high-end jewelry and industrial applications for cutting, grinding, and drilling due to extreme hardness.

Geological facts

Diamond is the hardest natural substance on Earth. Most natural diamonds are between 1 billion and 3.5 billion years old. Famous specimens include the Hope Diamond and the Cullinan Heritage.

Field identification & locations

Identified by its high brilliance, fire (dispersion), and extreme hardness. In the field, it is often found in alluvial deposits or within kimberlite pipes. Always verify with a diamond tester for accuracy.