mineral

Diamond (or Diamond Simulant/Cubic Zirconia)

Carbon (C) - if diamond, or Zirconium dioxide (ZrO2) - if Cubic Zirconia

If Diamond: Hardness 10 (Mohs), colorless to various colors, adamantine luster, isometric crystal structure, perfect cleavage in 4 directions. If CZ: Hardness 8-8.5, colorless, vitreous to subadamantine luster, isometric structure.

Identified April 27, 2026More mineral →

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Physical properties

Formation & geological history

Diamonds form in the Earth's mantle under high pressure and temperature over billions of years, brought to the surface by kimberlite eruptions. CZ is typically lab-created.

Uses & applications

Jewelry (faceted into varying cuts like the pear shape shown), industrial abrasives, cutting tools.

Geological facts

Diamond is the hardest known natural material. It has exceptional thermal conductivity. The pear shape cut is a modification of the round brilliant cut.

Field identification & locations

Identify diamond by its exceptional hardness (scratches sapphire), high refractive index, and thermal conductivity (using a diamond tester). Found in Russia, Botswana, Canada, South Africa.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral