Diamond (set in a gold ring)

Physical Properties

Hardness: 10 (Mohs scale), Color: Colorless (most common for jewelry, though can be blue/gray/yellow), Luster: Adamantine, Crystal Structure: Isometric-Hexoctahedral (Cubic), Cleavage: Octahedral, Specific Gravity: 3.51

Formation & Geological History

Formed under extreme high pressure and temperature conditions in the Earth's mantle, approximately 100 miles below the surface. They are brought to the surface through volcanic eruptions known as kimberlite or lamproite pipes.

Uses & Applications

Primary use in fine jewelry as a gemstone; industrial uses include cutting tools, grinding wheels, and drills due to extreme hardness.

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 word diamond comes from the Greek word 'adamas', meaning invincible.

Field Identification & Locations

Identification in the field is difficult as they resemble quartz or topaz, but they can be distinguished by their thermal conductivity and ability to scratch any other material. Typically found in kimberlite pipes or alluvial deposits.

Identified on: 4/21/2026

Mode: Standard