Cubic Zirconia

Other than natural diamonds, there is the problem of cubic zirconia or CZ. It is usually sold under a trade name such as Zirconia, Phyanite and Diamonique. Technically, CZ is not a synthetic diamond but it is a crystallization of the chemical zirconium that, when cut, has most of the optical characteristics of a diamond.

CZ is not as hard as a diamond and it does have a different specific gravity. It takes 1.70 carat CZ to equal 1 carat diamond in weight.

CZs, however, in the last few years, have become increasingly close to diamonds and good CZs are impossible to tell from diamonds by the eye. In fact, we had several gemologists look at unmounted CZ and unmounted diamonds, and they admitted they could not tell the difference. The only one who did pick out the CZ with some regularity was because, he said, the stones were too flawless to be diamonds. Hardly a reliable way to judge stones.

As one can see, the potential for fraudulent misuse of CZ is quite high and there have been a number of occasions where people were sold CZ instead of diamonds, turned their diamond rings into unscrupulous jewelers or gemologists, only to have CZ put in the same mountings and returned to them. There have been a number of cases of people looking at diamonds in a jewelry store, and with a quick distraction, replacing the diamond in full view of the jeweler with a CZ and giving that back instead. These will pass on sight.  How do you tell a CZ from a diamond? Well, luckily technology has come to the rescue. There are a number of devices on the market that, for under $150, will electronically test the material to see if it is a diamond or not. Diamonds have unique electrical resistance patterns and CZ have their own. These devices are simply touched to the material in question and will tell if it is a diamond or a CZ. It is a good thing to have on hand if one plans on dealing in gems.