mineral

Rough Diamond

Diamond (Pure Carbon: C)

Hardness: 10 (Mohs scale); Color: Pale yellowish-green (apple green); Luster: Adamantine to greasy in rough form; Crystal Structure: Isometric-hexoctahedral; Cleavage: Perfect in four directions (octahedral); Specific Gravity: 3.52.

Hardness: 10 (Mohs scale)
Color: Pale yellowish-green (apple green)
Luster: Adamantine to greasy in rough form

Identified March 28, 2026More mineral →

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Physical properties

Formation & geological history

Formed under extreme pressure and high temperature in the Earth's mantle (about 90-120 miles deep). They are transported to the surface via deep-seated volcanic eruptions called kimberlite or lamproite pipes. Most diamonds range from 1 to 3.5 billion years old.

Uses & applications

Predominantly used for industrial cutting, grinding, and drilling tools due to extreme hardness. Gem-quality specimens are used in jewelry. Small rough specimens are often sold as 'conflict-free' natural keepsakes or used in specialized rough-diamond jewelry.

Geological facts

Diamond is the only gemstone made of a single element (carbon). Despite its supreme hardness, it is brittle and can be shattered with a hammer. The green tint in some rough diamonds is often the result of exposure to natural radiation during their time in the Earth's crust.

Field identification & locations

Identify in the field by its characteristic greasy luster, triangular 'trigon' growth marks on faces, and inability to be scratched by any other material. Commonly found in South Africa, Russia, Canada, and Australia. Collectors should look for distinct octahedral shapes and natural skin translucency.