gemstone

Diamond

Carbon (C)

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

Identified July 3, 2026More gemstone →

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Physical properties

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

Formation & geological history

Formed under high-pressure, high-temperature conditions in the Earth's mantle, approximately 100 miles below the surface, and brought to the surface by deep-origin volcanic eruptions (kimberlite or lamproite pipes).

Uses & applications

Primary use in high-end jewelry (engagement rings) and industrial applications for cutting, drilling, and grinding due to extreme hardness.

Geological facts

Diamond is the hardest natural substance known on Earth. Most natural diamonds were formed between 1 billion and 3.5 billion years ago. The 'four Cs' (Cut, Color, Clarity, and Carat weight) determine a specimen's quality.

Field identification & locations

Identified by its unmatched hardness, brilliance, and high thermal conductivity. Commonly found in alluvial deposits or kimberlite pipes in regions like South Africa, Russia, Canada, and Botswana.