gemstone

Diamond (Round Brilliant Cut)

Carbon (C)

Hardness: 10 (Mohs scale); Color: Colorless (in this specimen); Luster: Adamantine; Crystal Structure: Isometric (Cubic); Specific Gravity: 3.52; Cleavage: Perfect in four directions.

Hardness: 10 (Mohs scale)
Color: Colorless (in this specimen)
Luster: Adamantine

Identified July 16, 2026More gemstone →

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Physical properties

Hardness: 10 (Mohs scale); Color: Colorless (in this specimen); Luster: Adamantine; Crystal Structure: Isometric (Cubic); Specific Gravity: 3.52; Cleavage: Perfect in four directions.

Formation & geological history

Formed deep within the Earth's mantle (100+ miles deep) under extreme high pressure and temperature over billions of years, then brought to the surface by explosive volcanic eruptions called kimberlite pipes.

Uses & applications

Predominantly used in high-end jewelry (engagement rings, necklaces); also used extensively in industrial applications for cutting, grinding, and drilling due to its extreme hardness.

Geological facts

Diamond is the hardest known natural material on Earth. The name comes from the Greek word 'adamas', meaning unbreakable. Most natural diamonds are between 1 billion and 3.5 billion years old.

Field identification & locations

Identify by its exceptional brilliance and fire (dispersion of light). In the field, look for octahedral crystals in blue ground (kimberlite). Professionals use thermal conductivity probes or loupes to check for inclusions and facet crispness.