gemstone

Diamond (in Jewelry)

Carbon (C)

Hardness: 10 (Mohs scale); Color: Colorless to faint yellow; Luster: Adamantine; Crystal Structure: Isometric (cubic); Cleavage: Perfect in four directions; Specific Gravity: 3.51

Hardness: 10 (Mohs scale)
Color: Colorless to faint yellow
Luster: Adamantine

Identified July 12, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale); Color: Colorless to faint yellow; Luster: Adamantine; Crystal Structure: Isometric (cubic); Cleavage: Perfect in four directions; Specific Gravity: 3.51

Formation & geological history

Formed under high-pressure, high-temperature conditions deep within the Earth's mantle, approximately 100 miles below the surface, usually over 1 to 3 billion years ago. They are brought to the surface via volcanic pipes called kimberlites.

Uses & applications

Primary use is in high-end jewelry (rings, necklaces, earrings). Industrial uses include cutting, grinding, and drilling tools due to extreme hardness.

Geological facts

Diamonds are the hardest natural substance known on Earth. The name comes from the Greek word \"adamas,\" meaning indestructible. Most natural diamonds were formed over a billion years ago.

Field identification & locations

Identification in the field requires specialized tools like loupes for looking at inclusions or thermal conductivity testers. Natural sources include South Africa, Russia, Canada, and Australia.