Diamond

Diamond (pure Carbon, C)

Rock Type: mineral

Diamond

Physical Properties

Hardness: 10 (Mohs scale), Color: Colorless (as shown), Luster: Adamantine, Crystal structure: Isometric-hexoctahedral (cubic), Cleavage: Perfect in four directions, Specific gravity: 3.52

Formation & Geological History

Formed deep within the Earth's mantle under extreme pressure and temperature over billions of years; brought to the surface via deep-seated volcanic eruptions called kimberlite or lamproite pipes.

Uses & Applications

Predominantly used in jewelry (rings, necklaces), and industrially for cutting, grinding, and drilling due to its extreme hardness.

Geological Facts

Diamonds are the hardest natural substance known on Earth. Most natural diamonds were formed between 1 billion and 3.5 billion years ago. The '4 Cs' (Cut, Color, Clarity, and Carat) determine a diamond's quality.

Field Identification & Locations

Identify by its ability to scratch any other material and its high refractive index (brilliance). In the field, they are often found in kimberlite pipes or alluvial deposits. Collectors look for unique crystal habits and inclusions.

Identified on: 5/1/2026

Mode: Standard