gemstone

Diamond (Rough)

Carbon (C)

Hardness 10 on Mohs scale, adamantine luster, isometric/cubic crystal system (often octahedrons or dodecahedrons), perfect octahedral cleavage, specific gravity 3.52, color ranges from colorless to pale yellow or brown.

Identified July 22, 2026More gemstone →

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Physical properties

Formation & geological history

Formed under extreme pressure and high temperatures deep in Earth's mantle (150-200 km down) over billions of years, brought to the surface via deep-source volcanic eruptions forming kimberlite or lamproite pipes.

Uses & applications

Used widely in high-end fine jewelry, cutting tools, industrial abrasives, drill bits, optical components, and quantum computing materials.

Geological facts

Diamond is the hardest naturally occurring substance known to science. Most natural diamonds are between 1 billion and 3.5 billion years old.

Field identification & locations

Identified by extreme hardness, adamantine luster, trigons (triangular growth markings) on octahedral faces, and high thermal conductivity. Commonly found in Russia, Botswana, Canada, Australia, and South Africa.