Cubic Zirconia and Zircon
January 17, 2008 - 11:28pm
Cubic Zirconia is a relatively new arrival on the jewelry scene. This material, first developed in its current state in the early 1970’s, became commercially available in 1976.
Cubic Zirconia has no true natural counterpart, and is not a synthetic version of natural zircon. It is a man made version of zirconium oxide. There are several naturally occurring zirconium oxides, none of which have any commercial importance, and none of which are used in jewelry.
Cubic Zirconia and Zircon have different optical characteristics and can usually be separated under magnification. Zircon is doubly refractive. When looking through the stone under magnification you will see that the back facet junctions of the stone appear twice; they are “doubled”. Cubic Zirconia does not have this characteristic. Natural Zircon is a zirconium silicate.
Cubic Zirconia may be produced in a wide range of colors. It may also be treated with a coating of diamond-like carbon film, making its visual appearance more similar to diamond. It may also be treated with coatings of metal oxides, giving it an iridescent “mystic” effect.
The double refraction of natural zircon may give it a “fuzzy” appearance, compared to either Diamond or Cubic Zirconia. Cubic Zirconia’s dispersion may give it a flash of spectral color that is not seen in the other two. Cubic Zirconia may be separated from diamond easily by weight, if the stone is unset, as it is much denser. A Cubic Zirconia the size of a 1-carat diamond will weigh about 1 ¾ carats. Cubic Zirconia will not exhibit some of the distinctive clarity characteristics and inclusions that diamond may exhibit. Diamond and Cubic Zirconia may have a different appearance under ultraviolet lighting. Many diamonds exhibit a blue fluorescence under ultraviolet light, which is normally stronger under long-wave ultraviolet lighting. Under long-wave ultraviolet, colorless Cubic Zirconia will normally fluoresce an orange-yellow color.
Cubic Zirconia has gained wide acceptance as a diamond simulant. It should not be represented as a synthetic form of natural Zircon. It should never be represented as a synthetic diamond or as a man made diamond. It is a totally different material and should be represented as a diamond simulant, if a comparison to diamond must be made.