gemstone

Diamond

Carbon (C)

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Isometric-Hexoctahedral, Cleavage: Octahedral (perfect in four directions), Specific Gravity: 3.52

Identified July 8, 2026More gemstone →

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Physical properties

Formation & geological history

Formed under extreme high pressure and high temperature conditions in the Earth's mantle, approximately 100 miles underground, and brought to the surface by deep-origin volcanic eruptions called kimberlites. Geological age ranges from 1 to 3.5 billion years.

Uses & applications

Primarily used in high-end jewelry (solitaires, pendants, rings) and industrially as an abrasive for cutting, drilling, and grinding due to its extreme hardness.

Geological facts

Diamond is the hardest naturally occurring substance on Earth. It is composed of a single element (carbon) arranged in a crystal lattice that provides its unique strength.

Field identification & locations

Identify by its exceptional brilliance, fire (dispersion), and ability to scratch any other material. In the field, they are found in kimberlite pipes or alluvial deposits. Standard identification for jewelry involves thermal conductivity testing and magnification to view inclusions.