mineral

Rough Diamond

Native Carbon (C)

Hardness: 10 (Mohs scale); Color: Colorless, yellow, or brown; Luster: Adamantine to greasy (in rough state); Crystal Structure: Isometric (cubic/octahedral); Cleavage: Perfect in four directions; Specific Gravity: 3.52.

Hardness: 10 (Mohs scale)
Color: Colorless, yellow, or brown
Luster: Adamantine to greasy (in rough state)

Identified March 14, 2026More mineral →

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Physical properties

Formation & geological history

Formed deep in the Earth's mantle (150-250 km) under extreme pressure and temperature. Transported to the surface by kimberlite or lamproite volcanic eruptions. Most specimens are 1 to 3.3 billion years old.

Uses & applications

Primary use in high-end jewelry (when cut/polished); significant industrial use for cutting, grinding, and drilling tools; specialized use in scientific high-pressure anvil cells.

Geological facts

Diamond is the hardest natural substance known to man. Rough stones often look like oily pebbles or shards of glass and do not exhibit their signature 'sparkle' until they are faceted.

Field identification & locations

Identify in the field by high specific gravity and the 'grease' test (diamonds attract grease/oil and repel water). Found globally in kimberlite pipes (South Africa, Russia, Canada) and alluvial deposits (riverbeds). Look for isometric triangular 'trigons' (etch marks) on the surface of the crystal faces.