gemstone
Diamond
Carbon (C)
Hardness of 10 on the Mohs scale, transparent to opaque, adamantine luster, isometric (cubic) crystal system, perfect octahedral cleavage, specific gravity of 3.50-3.53.
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Physical properties
Hardness of 10 on the Mohs scale, transparent to opaque, adamantine luster, isometric (cubic) crystal system, perfect octahedral cleavage, specific gravity of 3.50-3.53.
Formation & geological history
Formed under high-pressure and high-temperature conditions at depths of 140 to 190 kilometers in the Earth's mantle. Brought to the surface via deep-source volcanic eruptions of kimberlite and lamproite magmas, mostly ranging from 1 to 3 billion years old.
Uses & applications
Widely used in fine jewelry, engagement rings, industrial cutting tools, abrasive powders, and high-precision scientific equipment.
Geological facts
Diamonds are the hardest known natural substance on Earth. Despite being made purely of carbon, they form under conditions found only in the deep mantle.
Field identification & locations
Identified by extreme hardness (scratches all other minerals), high refractive index, and adamantine luster. Commonly mined in Russia, Botswana, Canada, and South Africa.
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