mineral

Rough Diamond

Diamond (Native Element Carbon, C)

Hardness: 10 (Mohs scale); Color: Pale yellow or cognac; Luster: Adamantine to greasy; Crystal structure: Cubic (often octahedral as seen here); Cleavage: Perfect octahedral; Specific Gravity: 3.52

Hardness: 10 (Mohs scale)
Color: Pale yellow or cognac
Luster: Adamantine to greasy

Identified May 9, 2026More mineral →

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Physical properties

Hardness: 10 (Mohs scale); Color: Pale yellow or cognac; Luster: Adamantine to greasy; Crystal structure: Cubic (often octahedral as seen here); Cleavage: Perfect octahedral; Specific Gravity: 3.52

Formation & geological history

Formed under extreme pressure and temperature deep within the Earth's mantle (100+ miles deep) over billions of years, then transported to the surface via kimberlite or lamproite volcanic pipes.

Uses & applications

Primary use in jewelry when cut; industrial grade used for cutting, grinding, and drilling due to extreme hardness.

Geological facts

Diamonds are the hardest natural substance known. This specific specimen shows the classic trigon growth marks and octahedral shape typical of rough stones from alluvial or pipe deposits.

Field identification & locations

Identify by extreme hardness (scratches everything else), greasy luster on uncut surfaces, and octahedral crystal habit. Commonly found in South Africa, Russia, Canada, and Australia.