mineral

Diamond

Carbon (C)

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Cubic, Specific Gravity: 3.52

Luster: Adamantine, Crystal Structure: Cubic, Specific Gravity: 3

Identified June 18, 2026More mineral →

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Physical properties

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Cubic, Specific Gravity: 3.52

Formation & geological history

Formed under high-pressure, high-temperature conditions deep within the Earth's mantle, approximately 90 to 120 miles below the surface. They are brought to the surface by kimberlite and lamproite volcanic eruptions. Most are 1 to 3 billion years old.

Uses & applications

Primary use in jewelry such as the engagement ring pictured. Industrially used for cutting, drilling, and grinding tools due to extreme hardness.

Geological facts

Diamonds are the hardest known natural substance. The name comes from the Greek word 'adamas', meaning invincible. They are the only gemstone made of a single element: Carbon.

Field identification & locations

Identified by their high refractive index (sparkle), hardness (will scratch glass/steel), and thermal conductivity. Commonly found in South Africa, Russia, Canada, and Australia. In the field, they are sought in kimberlite pipes or alluvial deposits.