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Cubic zirconia (CZ) is a diamond look-alike that costs a fraction of what a diamond does. CZ is almost as durable as a diamond. On the Moh’s Scale of Hardness, a diamond is rated at 10. Cubic zirconia is rated at 8.5. Opals rank at 5 and gypsum ranks at 2, which gives you an idea of where CZs rank in comparison to other gems.

Harmful Chemicals

Even though cubic zirconia is a durable stone, there are some chemicals that should be avoided, if you want your stone to last. Skin oils, dirt and soap can leave a residue on your stone that makes it look dull. If these substances are on the underside of the stone, it can even look opaque. Household chemicals, such as bleach, ammonia, chlorinated water and scouring powder are damaging to cubic zirconia.


CZ is more brittle than a diamond and, therefore, more susceptible to breakage from impact. If hit hard enough, a cubic zirconia can break into pieces. Even if this happens, though, you would only have to pay $10 to $200 to replace it, depending on the CZ’s size. Replacing a diamond would be much more costly.

Warn the Jeweler

If you take your cubic zirconia to the jeweler for cleaning or resetting, make sure he knows that the stone is a CZ and not a diamond. The way he sets and cleans a CZ is different than it is for a diamond. The flame that a jeweler uses for ring sizing would shatter a cubic zirconia.

Care of Cubic Zirconia

You should clean your CZ jewelry at least once a week if you wear it all the time. Soak it in a mild detergent-and-water solution for five minutes and then rinse it thoroughly with warm water. Lay it on a folded hand towel and blot it with another. Put lotion on your hands before slipping on your ring. After you have rubbed in the lotion, blot the excess off your hands with a towel.