Cubic Zirconia

Cubic Zirconia is a synthetic (man-made) gemstone used as an inexpensive alternative to diamonds.  It is made from the cubic crystalline form of zirconia dioxide.  This is also where it gets its name "Cubic Zirconia".

Referred to as imitation diamonds or CZ diamonds, Cubic Zirconia was discovered as  a natural mineral in 1937.  It wasn't until lthe 1970s that it started to be used in the jewellery industry as an alternative to diamonds.  

How hard is a Cubic Zirconia

Gemstones and minerals are measured for hardness and durability of a scale referred to as the Mohs Hardness Scale.  The values on this scale range from 1 being the softest through to 10.  True natural diamonds sit at the top of this scale at 10.  Cubic Zirconia sits at 8 - 8.5 on the Mohs scale. 

This may not seem a huge difference in hardness, but eventually cubic zirconia stones will scratch and lose their shine over time - depending on how often they are worn and in what conditions.  Earrings for instance, may last much longer than rings which may be subject to much more knocks and movement. However, if cost is a consideration in purchasing jewellery, imitation diamonds are perfectly fine as long as you remember that they may not last forever. 

Is a Cubic Zirconia lab-grown?

A cubic zirconia does not have the same chemical properties as a natural diamond (like a lab-grown diamond would).  Natural and lab-grown diamonds are made from carbon.  Cubic Zirconia is made by heating and melting zirconium dixode (ZrO2) with stablisers and then cooled.   When the chemicals  have cooled they harden into a rock form and can be cut and polished into different shapes and sizes, just like any other gemstone. 

What is the colour of Cubic Zirconia?

Natural diamonds with a "D" colour are very rare and colourless.  Most diamonds have a yellow or brown tint to them and are scaled according to the amount of imperfections in the stone.  Cubic Zirconia however,  is completely clear.

Cubic Zirconia can also be treated with different elements in the manufacturing process to create stones of any colour.  Adding Chromium creates a green colour,