Cubic Zirconia

Usually colorless; can be produced in many colors.

Blue Colorless Green Pink Purple Red Yellow

Optical properties

Optical characteristics

Ref. index: 2.15 – 2.18
Luster: Sub-adamantine to adamantine
Pleochroism: None None; singly refractive.
Fluorescence: Variable; often inert to weak yellow, orange, or blue depending on material.

Origins

Synthetic/lab-created material rather than a natural mine origin.

Inclusions

Identification

Specifications

Market price $ 1 – 20+ / ct

Cubic zirconia is a low-cost synthetic diamond simulant; large stones remain inexpensive.

Rarity Very Common

Cubic zirconia is synthetic and extremely common as a diamond simulant.

Confused with

Glass Look for bubbles, mold marks, and low hardness.
Synthetic counterpart Synthetic materials may share properties but show different inclusions or growth features.
YAG Both are isotropic synthetic simulants sold in the same colorless market. YAG has much lower RI (1.833 vs 2.15-2.18) and lower SG (4.55-4.60 vs 5.65-5.95). A refractometer reading or hydrostatic weighing separates them immediately.
Moissanite Moissanite shows doubling of facet edges and is much lighter (SG 3.21) than CZ (SG 5.6–6.0)

Expert tip

Cubic zirconia is much heavier than diamond and moissanite. Its high SG is one of the fastest separation clues.