Diamond

Physical Properties

Hardness: 10 (Mohs scale), Color: Colorless (to yellow/brown/blue/pink), Luster: Adamantine, Crystal Structure: Isometric-Hexoctahedral, Cleavage: Octahedral (perfect in four directions), Specific Gravity: 3.51

Formation & Geological History

Formed under high-pressure, high-temperature conditions deep within the Earth's mantle (about 100 miles deep) and brought to the surface by kimberlite and lamproite pipes. Most diamonds are 1 to 3 billion years old.

Uses & Applications

Primary use in jewelry (gemstones) and industrial applications such as cutting tools, grinding wheels, and drill bits due to its extreme hardness.

Geological Facts

Diamond is the hardest known natural substance. The name comes from the Greek word 'adamas', meaning invincible. It is the only gemstone made of a single element (Carbon).

Field Identification & Locations

Identify in the field by its extreme hardness (cannot be scratched by any other material), high refractive index (brilliance), and specific gravity. Often found in kimberlite pipes or alluvial deposits.

Identified on: 4/27/2026

Mode: Standard