gemstone

Diamond (Cut and Polished)

Diamond (pure Carbon, C)

Hardness: 10 (Mohs scale), Color: Colorless to faint yellow/brown in this specimen, Luster: Adamantine, Crystal structure: Isometric-Hexoctahedral, Cleavage: Perfect in four directions forming octahedrons, Specific Gravity: 3.51

Identified July 10, 2026More gemstone →

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Physical properties

Formation & geological history

Formed at high pressure and temperature in the Earth's mantle (140-190 km deep) and transported to the surface via kimberlite or lamproite volcanic pipes. Formation ages range from 1 to 3.3 billion years.

Uses & applications

Used primarily in fine jewelry (rings, earrings, necklaces) due to its brilliance and durability, and in industrial applications for cutting, grinding, and drilling tools.

Geological facts

Diamond is the hardest natural substance known to man. Highly valued diamonds are graded by the 'Four Cs': Carat, Color, Clarity, and Cut. The Hope Diamond is one of the most famous historical specimens.

Field identification & locations

Identification includes testing for high thermal conductivity (using a diamond tester), checking for refractive brilliance, and observing the 'fire' or dispersion of light. Commonly found in South Africa, Russia, Canada, and Australia.

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Amber

Succinite (Organic Gemstone)

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Citrine

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Tiger's Eye

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Amber

Succinrite (Organic Gemstone)

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