mineral

Diamond (set in jewelry)

Diamond (Carbon, C)

Hardness: 10 (Mohs scale), Color: Colorless (as shown), Luster: Adamantine, Crystal Structure: Isometric-Hexoctahedral, Cleavage: Perfect in four directions, Specific Gravity: 3.51

Identified April 21, 2026More mineral →

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Physical properties

Hardness: 10 (Mohs scale), Color: Colorless (as shown), Luster: Adamantine, Crystal Structure: Isometric-Hexoctahedral, Cleavage: Perfect in four directions, Specific Gravity: 3.51

Formation & geological history

Formed under high-pressure, high-temperature conditions in the Earth's mantle, typically at depths of 140 to 190 kilometers. Brought to the surface by deep-origin volcanic eruptions (kimberlite or lamproite pipes). Dating back 1 to 3.5 billion years.

Uses & applications

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

Geological facts

Diamonds are the hardest known natural material. The 'Cullinan' is the largest gem-quality rough diamond ever found, weighing 3,106 carats. Most natural diamonds are billions of years old.

Field identification & locations

Identify by extreme hardness and high refractive index (brilliance). In the field, look for octahedral crystals within kimberlite matrix. Note: This specimen is already cut and faceted for jewelry.