gemstone

Diamond

Natural Diamond (Carbon, C)

Hardness: 10 Mohs; Color: Colorless (in this specimen); Luster: Adamantine; Crystal Structure: Isometric (cubic); Cleavage: Perfect octahedral; Specific Gravity: 3.52

Hardness: 10 Mohs
Color: Colorless (in this specimen)
Luster: Adamantine

Identified July 10, 2026More gemstone →

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Physical properties

Hardness: 10 Mohs; Color: Colorless (in this specimen); Luster: Adamantine; Crystal Structure: Isometric (cubic); Cleavage: Perfect octahedral; Specific Gravity: 3.52

Formation & geological history

Formed under extreme pressure and temperature in the Earth's mantle (100+ miles deep) over billions of years, then transported to the surface by kimberlite volcanic eruptions.

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 known 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 (brilliance), extreme hardness, and ability to scratch any other material. Commonly found in kimberlite pipes or alluvial deposits in Africa, Russia, Canada, and Australia.