An Excellent Substitute To The Expensive Diamond Jewelry
by Fred Gagnon
cubic zirconia gold jewelry, silver cubic zirconia jewelry, sterling silver cubic zirconia jewelry, white gold cubic zirconia jewelry
Cubic zirconia jewelry is made with dazzling man-made crystal and an excellent substitute to the expensive diamond jewelry. It has extraordinary brilliance and luster, and like diamond jewelry, it will last forever. But, unlike diamond, cubic zirconia does not have flaws or inclusions.
Cubic zirconia or CZ is a cubic crystalline form created out of zircon and oxide fusion cooled under regulated conditions. The synthesized material is hard, naturally colorless and visually flawless, but maybe produced in variety of colors. Also called cubic zirconium, this synthetic gemstone is used as an alternative to diamond.
Cubic zirconia is oftentimes mistakenly called zircon. It shouldn’t be so because CZ is different from zircon. The chemical formula of zircon is ZrSiO4 for zirconium silicate, while for cubic zirconia is ZrO2 which stands for zirconium dioxide.
Two German mineralogists discovered CZ in 1937. Synthetic CS remains to be the most economically and gemologically important competitor for diamonds, since 1976. Soviet scientists “culture” this mineral inside the laboratory in the 70s. From then on, CZ became famous among jewelry makers not only because of its resemblance to diamond, but also because it is cheaper and durable.
Cubic zirconia is chemically comprised of zirconium oxide and yttrium oxide (sometimes calcium oxide). The two compounds are melted together at a very high temperature of almost 5,000F (2,760C) using the skull method. Then the zirconium oxide is heated using a radio frequency generator. And a careful cooling process or stabilizer is required for cubic crystal formation to be effected.
It is crystallographically isometric like diamond, which makes it an inexpensive alternative to diamond in jewelry making. Synthetic moissanite, the more recently cultured material, is the main competitor of CZ in synthetic gemstones.
There are key features that distinguish cubic zirconia from diamond (some can only be seen under the microscope or loupe).
Specific Gravity: Compared to diamond, cubic zirconia crystal is heavier. Cubic zirconia has a specific gravity that ranges from 5.6-6.0, while diamond’s specific gravity is 3.52. CZ weighs about 1.7 times more than a diamond of equivalent size.
Hardness: CZ maybe incomparable to diamond, but is much harder than most natural gems. The Moh’s hardness of diamond is 10, while cubic zirconia has a Moh’s hardness that is 8.5 to 9.0.
Reflective or Refractive Index: The reflective index for cubic zirconia is 2.15 to 2.18 while diamond’s is 2.4.
Luster: The luster of CZ is subadamantine, while adamantine for diamond.
Dispersion: The dispersive power of cubic zirconia is greater than that of diamond’s. CZ has a very high dispersion of 0.058-0.066, which far exceeded diamond’s 0.044. CZ has more prismatic fire visible even to the naked eye.
Cleavage: Cubic zirconia has no cleavage, while diamond has a cleavage plane. This makes a diamond more fragile in some orientations than CZ. However, both exhibit a conchoidal fracture.
Flaws: Most diamonds show evidence of multiple growth stages that produces defect planes, inclusions and flaws in the crystal lattice, while CZ is virtually flawless.
Cut: The facet shapes of some cubic zirconia are different compared to the diamond. They can be seen using a loupe which is a form of a modified microscope.
Color: Cubic zirconia can be made in most cases entirely colorless, while diamonds usually have a tinge of yellow. Truly colorless diamonds are very rare.
Thermal Conductivity: Cubic zirconia is not a thermal conductor like diamond. It is in fact thermal insulator. Diamonds can be identified by their high thermal conductivity, which even exceeds copper. With the right instrument, distinguishing the difference between CZ and diamond by thermal conductivity is easy.
