gemstone
Diamond (or Diamond Simulant)
Carbon (C) or Zirconium dioxide (ZrO2) for CZ
If diamond: Hardness 10, colorless to various colors, adamantine luster, isometric crystal structure, perfect cleavage in four directions. If cubic zirconia (simulant): Hardness 8-8.5, colorless, adamantine luster, isometric.
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Physical properties
If diamond: Hardness 10, colorless to various colors, adamantine luster, isometric crystal structure, perfect cleavage in four directions. If cubic zirconia (simulant): Hardness 8-8.5, colorless, adamantine luster, isometric.
Formation & geological history
Natural diamonds form deep in the Earth's mantle under extreme heat and pressure over billions of years and are brought to the surface by kimberlite eruptions. Simulants like CZ are lab-created.
Uses & applications
Jewelry, industrial cutting and grinding tools (for diamonds), optical components.
Geological facts
Diamonds are the hardest known natural material. It is impossible to tell from just a photo whether a small, loose, faceted clear stone is a diamond, cubic zirconia, white sapphire, or glass.
Field identification & locations
Identify using a diamond tester (thermal conductivity), examining facet edges under a loupe (diamonds have sharp edges, simulants often have worn or rounded edges), or by refractive index.
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