There is a difference between Moissanite and Cubic Zirconia. The basic similarity found in both is that they are both man-made stones.
Further, it is true that both of them are the diamond simulants that means they try to mimic the look and sense of genuine diamonds.
Hence there is a great difference between the two. If you compare Cubic Zirconia (CZ) with that of moissanite diamonds, then soon you will understand as per the range of features the stones are no real match for the later. The one chief most obvious advantage of cubic zirconia over moissanite is that they are relative to the low price.
According to the composition, Moissanite is silicon carbide. It is a compound having chemical formula SiC. While on the contrary, cubic zirconia is zirconium dioxide, with the chemical formula ZrO2. Moissanite is a proportionate composition of the material like silicon and carbon, while CZ or Cubic zirconia in its crystal lattice consists of zirconium and oxygen.
Diamond is an alternative to pure carbon. Cubic Zirconia and Hexagonal Zirconia if compared to diamond, then you will find moissanite composition much more closely to diamond. Moreover, moissanite is the result of replacing a few of the carbon atoms with silicon. In the crystal structure of diamond-silicon can be replaced with carbon as both have the almost same material valence and can be successfully accommodated in the same type of environment. Cubic Zirconia contains a relatively heavy constituent with totally different properties. It is however twice as much as moissanite's particular gravity.
You will find a hexagonal crystal structure in case of Moissanite, while the structure of CZ or cubic zirconia is of course cubic. That is the reason that Moissanite is not isometric. Rather unlike cubic zirconia or diamond, it is doubly refractive. The term double refractivity refers to the condition where each light ray which enters into the gemstone or crystal is decomposed into two rays, which of course contributes to the greater beauty of moissanite. It reflects a high brilliance of the refractive index as well as fire dispersion. But cubic Zirconia won't have such property.
Apart from this if you consider the optical properties of both the substances that are Cubic Zirconia and Moissanite, as per their brilliance and fire, then you will come to the conclusion that refractive index of moissanite is near about 2.7, which is closed to the refractive index of diamond (2.4) or cubic zirconia (2.15). The brilliance of the material simply speaks about the incident of the white light is being reflected back to your sight. However, the property is purely based on the artistry skill of cutting and polishing. And the term fire denotes to their light dispersing aspect, it has been seen that moissanite has a dispersion of 0.1 which is much more than of cubic Zirconia having merely 0.06. That means both of them are higher fire than diamond which is simply 0.04.
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