mineral (synthetic)

Cubic Zirconia (CZ)

Cubic Zirconium Dioxide (ZrO2)

Hardness: 8.0–8.5 (Mohs); Color: Colorless (in this specimen); Luster: Adamantine; Crystal structure: Isometric (Cubic); Specific Gravity: 5.6–6.0; Refractive Index: 2.15–2.18; Cleavage: None.

Hardness: 8
Color: Colorless (in this specimen)
Luster: Adamantine

Identified March 11, 2026More mineral (synthetic) →

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Physical properties

Hardness: 8.0–8.5 (Mohs); Color: Colorless (in this specimen); Luster: Adamantine; Crystal structure: Isometric (Cubic); Specific Gravity: 5.6–6.0; Refractive Index: 2.15–2.18; Cleavage: None.

Formation & geological history

Synthetically produced in a laboratory using the skull melting process. While baddeleyite (natural ZrO2) exists, it is monoclinic; the cubic form is stabilized with oxides like yttrium or calcium during high-heat crystallization.

Uses & applications

Primary use as a diamond simulant in jewelry due to its high dispersion and brilliance; also used in optical applications and for industrial cutting tools.

Geological facts

CZ is a 'diamond simulant' but not a 'synthetic diamond' (which is pure carbon). It is heavier than diamond, weighing approximately 1.7 times more for a stone of the same size.

Field identification & locations

Identify by its lack of natural inclusions under magnification, its higher weight (specific gravity) compared to diamond, and high dispersion 'fire.' Found in nearly all retail jewelry stores globally.

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Cubic Zirconia (CZ)

Cubic Zirconium Dioxide (ZrO2)

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Cubic Zirconia (CZ)

Cubic Zirconium Dioxide (ZrO2)

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