Rough Diamond

Physical Properties

Hardness: 10 (Mohs scale), Color: Colorless to faint yellow/brown in rough form, Luster: Adamantine to greasy (when rough), Crystal Structure: Isometric-hexoctahedral, Cleavage: Perfect in four directions, Specific Gravity: 3.51

Formation & Geological History

Formed deep within the Earth's mantle (150-250 km deep) under extreme high pressure and temperature. They are brought to the surface via deep-source volcanic eruptions called kimberlite or lamproite pipes, often dating back 1 to 3.5 billion years.

Uses & Applications

Primary use in high-end jewelry after cutting/polishing. Industrial uses include cutting tools, abrasives, drilling bits, and specialized optical windows due to its unmatched hardness.

Geological Facts

Diamonds are the hardest known natural substance. The name comes from the Greek word 'adamas,' meaning unbreakable. Most natural diamonds are billions of years old.

Field Identification & Locations

Identify in the field by its extreme hardness (cannot be scratched by any other mineral) and its isometric crystal habit (octahedrons are common). Often found in kimberlite pipes or alluvial deposits (riverbeds).

Identified on: 4/20/2026

Mode: Standard