gemstone

Diamond (or Cut Gemstone / Cubic Zirconia)

Carbon (C)

Hardness: 10 on Mohs scale (if natural diamond). Color: Colorless/transparent with high dispersion (fire). Luster: Adamantine. Crystal System: Cubic/Isometric (when uncut); this specimen is cut into a round brilliant shape. Specific Gravity: ~3.52.

Hardness: 10 on Mohs scale (if natural diamond)
Color: Colorless/transparent with high dispersion (fire)
Luster: Adamantine

Identified July 24, 2026More gemstone →

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Physical properties

Formation & geological history

Natural diamonds form deep within the Earth's mantle (150-200 km deep) under high pressure and temperature over billions of years, brought to the surface via kimberlite and lamproite pipes.

Uses & applications

Extensively used in fine jewelry (rings, necklaces) and industrially as abrasives, cutting tools, drill bits, and high-precision optics.

Geological facts

Diamond is the hardest naturally occurring material on Earth. Synthetic diamond simulants like Cubic Zirconia (CZ) or Moissanite closely imitate its brilliant appearance and high refractive index.

Field identification & locations

A visual identification of a cut clear stone cannot definitively distinguish natural diamond from laboratory-grown diamond, cubic zirconia, white sapphire, or moissanite. Thermal conductivity testing or specific optical testing under magnification is required for certainty.

Other gemstone specimens

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Diamond and Gold Jewelry

Carbon (Diamond) / Au (Gold)

gemstone

Ammolite

Ammolite (Biogenic Aragonite with trace elements; fossils of Placenticeras meeki and Placenticeras intercalare)

mineral

Cubic Zirconia (simulant) or Diamond

ZrO2 (Cubic Zirconia) or C (Diamond)

gemstone

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

sedimentary

Cubic Zirconia (or possibly Diamond)

Zirconium dioxide (or Carbon)

gemstone

Faceted Gemstone

Unknown transparent mineral, possibly Diamond (C), Cubic Zirconia (ZrO2), Quartz (SiO2), or Glass

gemstone