mineral

Diamond

Diamond (pure carbon, C)

Hardness: 10 (Mohs scale); Color: Colorless (in this specimen), can be yellow, brown, or blue; Luster: Adamantine; Crystal Structure: Isometric-Hexoctahedral; Cleavage: Perfect in four directions; Specific Gravity: 3.51

Hardness: 10 (Mohs scale)
Color: Colorless (in this specimen), can be yellow, brown, or blue
Luster: Adamantine

Identified April 2, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Formation & geological history

Formed under high-pressure, high-temperature conditions in the Earth's mantle, typically at depths of 150-250 kilometers, and transported to the surface by kimberlite or lamproite volcanic eruptions.

Uses & applications

Primary use in jewelry as gemstones; industrial uses include cutting, grinding, and drilling tools due to extreme hardness; high-end heat sinks in electronics.

Geological facts

Diamonds are the hardest known natural material on Earth. Most natural diamonds were formed between 1 billion and 3.5 billion years ago. The 'Cullinan' is the largest gem-quality rough diamond ever found.

Field identification & locations

Identify by its ability to scratch any other material and its high refractive index (brilliance). Found in primary deposits (kimberlite pipes) or secondary alluvial deposits (riverbeds). Collectors look for 'the four Cs': Carat, Cut, Color, and Clarity.