gemstone

Diamond

Carbon (C)

Hardness: 10 on the Mohs scale, Color: Colorless to yellow, brown, blue, pink, etc., Luster: Adamantine, Crystal Structure: Isometric (cubic), Cleavage: Perfect octahedral cleavage, Specific Gravity: 3.50-3.53

Color: Colorless to yellow, brown, blue, pink, etc

Identified July 28, 2026More gemstone →

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Physical properties

Formation & geological history

Formed under high-pressure and high-temperature conditions deep within the Earth's mantle (typically 150-200 kilometers deep) and brought to the surface through deep-seated volcanic eruptions of kimberlite and lamproite magmas. Geological age ranges from 1 billion to over 3 billion years.

Uses & applications

Widely used in high-end jewelry, engagement rings, and various industrial applications such as cutting, grinding, drilling, and polishing tools due to its extreme hardness.

Geological facts

Diamond is the hardest naturally occurring substance on Earth. Despite being made entirely of carbon, it is structurally distinct from graphite, which is also made of carbon but is extremely soft.

Field identification & locations

Identified by its supreme hardness, high refractive index, and brilliant adamantine luster. Natural diamond specimens can be found in kimberlite pipes around the world, notably in South Africa, Russia, Canada, and Australia.