Diamond (set in jewelry)

Diamond (Carbon, C)

Rock Type: mineral

Diamond (set in jewelry)

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.

Identified on: 4/21/2026

Mode: Standard