Last updated on March 9, 2021
People think it’s really hard to tell real diamonds from simulants. In fact, some signs can help you to spot the difference between cubic zirconia and diamonds even if you are not an expert in gemology.
Cubic Zirconia Has No Inclusions
One of the most obvious differences between these two stones is that cubic zirconia is literally flawless. Since it is created artificially in labs, cubic zirconia doesn’t have any inclusions.
Cubic Zirconia is Less Durable
Cubic zirconia is made of synthetic materials and it is not as hard as a real diamond. On the Mohs scale of hardness, it has a value of 8.5 while diamond is graded 10.
Since cubic zirconia is less durable it scratches more easily and looks worn and dull with time. Keep in mind that it’s more prone to chipping and requires more care as a result. However, this may not be a big issue since it’s cheap and you can always buy a new stone to replace the damaged one.
If you compare a real diamond with cubic zirconia under magnification, you will notice that the diamond has very sharp edges.
In contrast, the facets of cubic zirconia will have smoother and rounded edges. Since it’s not as hard as a diamond, cubic zirconia can not be cut and faceted to match a real diamond cut.
Cubic Zirconia is Colourless and Fiery
Good news for you. Cubic zirconia is virtually colourless and has no tints or hues. Its colour corresponds to the highest colour grades possible (D-E-F). That is why if you buy cubic zirconia, you don’t need to worry about yellow tints.
If you are a big fan of intense play of colour, this stone may be a good choice for you. Cubic zirconia is extremely fiery, meaning it shines in all colours of the rainbow.
This is also a good way to tell cubic zirconia apart from a diamond. The first produces more fire and brilliance and it’s a lot more colourful than a real diamond.
Cubic Zirconia has Lower Heat Conductivity
Cubic zirconia and diamonds completely differ in the way they conduct heat. The easiest way to tell these two stones apart is to use a diamond tester.
However, there is still another method to test if you don’t have the tool around.
If you breathe on the stone and the fog from your breath disappears right away, it’s a real diamond. If you do the same test with cubic zirconia, the stone will remain foggy for a longer time, indicating you are dealing with a simulant.
Also, since cubic zirconia has lower heat conductivity, it can easily crack and burn under high temperature.
Cubic Zirconia is Heavier
Diamonds weigh less than cubic zirconia.
If you compare two stones of the same size, the cubic zirconia will be much heavier than the diamond, about twice as heavy to be exact.
Cover image credit: The Diamond Works