gemstone

Diamond

C (Carbon)

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal structure: Cubic (Isometric), Cleavage: Perfect in four directions, Specific gravity: 3.52.

Identified July 12, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal structure: Cubic (Isometric), Cleavage: Perfect in four directions, Specific gravity: 3.52.

Formation & geological history

Formed under extreme heat and pressure conditions in Earth's mantle, approximately 100 to 150 miles deep. Transported to the surface by deep-origin volcanic eruptions known as kimberlite or lamproite pipes.

Uses & applications

Primarily used in high-end jewelry and industrial applications for cutting, grinding, and drilling due to its extreme hardness and thermal conductivity.

Geological facts

Diamonds are the hardest natural substance known on Earth. Many famous diamonds, like the Hope Diamond, have storied histories. They are billions of years old, often dating back 1 to 3 billion years.

Field identification & locations

Identify by its brilliance, dispersion (fire), and inability to be scratched by any other material. Commonly found in alluvial deposits or kimberlite pipes in Africa, Russia, Canada, and Australia.