gemstone

Diamond

Diamond (C - Pure Carbon)

Hardness: 10 on the Mohs scale (hardest known natural substance). Color: Colorless to white. Luster: Adamantine (brilliant, high refractive index of 2.42). Crystal System: Isometric/Cubic. Cleavage: Perfect octohedral cleavage in 4 directions. Specific Gravity: 3.51-3.53.

Hardness: 10 on the Mohs scale (hardest known natural substance)
Color: Colorless to white
Luster: Adamantine (brilliant, high refractive index of 2

Identified July 24, 2026More gemstone →

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Physical properties

Formation & geological history

Formed under extreme temperatures (1100°C - 1300°C) and pressures at depths of 150 to 200 kilometers within Earth's mantle over millions to billions of years. Transported to the surface by deep-origin volcanic eruptions in kimberlite and lamproite pipes.

Uses & applications

Widely used in fine jewelry (engagement rings, gemstone settings) due to unmatched brilliance and durability. Also heavily used in industrial applications such as cutting, grinding, drilling, and thermal management due to supreme hardness and thermal conductivity.

Geological facts

Diamond is composed of pure elemental carbon arranged in a strong covalent lattice. While natural diamonds originate in deep mantle pipes or alluvial placer deposits, synthetic diamonds (cubic zirconia, moissanite, or lab-grown diamonds) are frequently crafted in round brilliant cuts like this specimen.

Field identification & locations

Identified by extraordinary hardness, adamantine luster, high dispersion (fire), and inability to be scratched by quartz or corundum. Found globally in kimberlite deposits (e.g., South Africa, Russia, Canada, Australia) and alluvial sands.