gemstone

Diamond (or Cut Clear Gemstone)

C (Native Carbon)

Hardness 10 on the Mohs scale (if natural diamond), Adamantine luster, cubic crystal system, isometric structure, extremely high thermal conductivity and strong dispersion (fire). Colorless and transparent.

Identified July 25, 2026More gemstone →

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Physical properties

Formation & geological history

Formed at extreme depths (150-200 km) in Earth's mantle under intense pressure (>45,000 atmospheres) and high temperature over billions of years, transported to the surface via deep-source kimberlite volcanic eruptions.

Uses & applications

Extensively cut and polished as a high-value gemstone for fine jewelry, high-end rings, and luxury ornaments. Industrial uses include precision cutting tools and abrasives.

Geological facts

Diamond is the hardest naturally occurring substance known on Earth. Faceted brilliant-cut diamonds exhibit incredible fire, brilliance, and scintillation due to high refractive index and dispersion.

Field identification & locations

Look for crisp facet junction edges, high brilliance, and adamantine luster. Can be distinguished from cubic zirconia or glass by thermal conductivity testing, specific gravity testing, or observing double refraction (if moissanite).