lab grown diamonds vs cubic zirconia

With all the gemstone options available for brides today, it can be confusing to keep them all straight and understand the differences between them. If you’re looking for the luster and sparkle of a diamond without the cost, you might encounter a common misconception: that lab grown diamonds and cubic zirconia are one and the same.

While they can seem similar from a distance, these stones could not be more different. To be blunt, cubic zirconia is not a diamond in any way. Lab grown diamonds, on the other hand, are real diamonds through and through. Here’s a helpful comparison between cubic zirconia and lab grown diamonds.

what is cubic zirconia?

Cubic zirconia (CZ) is an inexpensive, synthetic material that is created by melting zirconium oxide powder with stabilizers like calcium and magnesium. As it cools, its crystals form and stabilize, creating a product that can be cut and polished to mimic natural or lab grown diamond shapes such as round, princess, oval and cushion diamonds. Most notably, CZ also contains no carbon, which is one of the primary chemical properties of a real diamond. Since CZ shares no chemical or physical characteristics with real diamonds, it is a different material from diamonds entirely.

what is a lab grown diamond?

Unlike their natural diamond counterparts, lab grown diamonds are created above ground in dedicated facilities using responsibly sourced diamond seeds and specialized technology. Although the process is complex, the results are breathtaking: lab grown diamonds share identical chemical, physical and optical characteristics with natural diamonds. They’re made almost entirely of pure crystallized carbon. These lab grown stunners are then cut and polished to catch the light and sparkle beautifully, just like a natural diamond would.

lab grown diamonds vs cubic zirconia: what's the difference?

Lab grown diamonds and cubic zirconia may look similar at a distance, but they differ significantly in quality, beauty and value.


On the 10-point Mohs Hardness Scale — the industry-standard test used to grade a gemstone’s hardness or durability — cubic zirconia ranks 8 to 8.5, which means it can be scratched and become foggy over time. It also needs to be cleaned more often than a lab grown diamond. Lab grown diamonds, by comparison, score a perfect 10 on the Mohs Scale.


Although lab grown diamonds and cubic zirconia come in similar shapes, CZs will have inferior refractive qualities compared to lab grown diamonds, which have spectacular shine, fire and sparkle according to a particular cut.


Unlike lab grown diamonds, which can be made with varying degrees of color, cubic zirconia gives off a “rainbow effect,” which is a telltale sign it isn’t a real diamond. Lab grown diamonds are real diamonds, so you’d analyze their color, which ranges from D-Z (colorless to light yellow), according to the 4Cs.


From a value perspective, cubic zirconia is worth very little. It’s cheap to make and comes with a similarly inexpensive price tag. If you were to try and resell a CZ ring, you could retain some value for the setting, but the actual cubic zirconia gemstone carries little to no market value. This is reflected in the low cost of CZ, which can be about one one-hundredth the cost of a lab grown diamond. By comparison, one major benefit of lab grown diamonds is that you can get a real diamond for a lower price compared to a natural diamond of similar quality and carat weight.


CZ can be found in nature, but it’s incredibly rare. That’s why the CZ used in jewelry, which is made up of synthetic zirconium oxide and stabilizing materials, is exclusively man made.

Lab grown diamonds, on the other hand, are sourced from diamond seed crystals using either the HPHT or CVD growing methods. No matter which method scientists use, they are able to use sophisticated technology to create real diamonds in a matter of weeks.

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