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How to distinguish cubic zirconia and diamond (4 simple ways)

Views:83     Author:Messigems     Publish Time: 2020-03-18      Origin:Site

How to distinguish cubic zirconia and diamond (4 simple ways)

  How to distinguish cubic zirconia and diamond (4 simple ways)

  First of all, we know that a diamond has one unique feature -- its hardness. Diamonds have a Mohs hardness of 10, while cz has a Mohs hardness of 6-7. Therefore, we can use their hardness differences to distinguish . 

  Find a gem with a hardness in the middle of them and scratch it on the diamond and cz’s table. If diamond, then there will not be any scratches on the table; if cz stone , it’s table will be scratched. Don't think it's a shame that cz is scratched. Although cz can be regarded as a mid-range gem, but compared with you buying an fake diamond (that is cz) at a high price, don't worry about the little money.

 cz diamond

  Second, use perspective effect to distinguish diamond and CZ. Find a piece of paper with a black line, place the diamond and loose cz table on the bottom where the black line is drawn downwards. If it is a diamond, the black line will not be seen under it for the diamond is standard cut, which means that there is almost no light can pass through the pavilion facet (except in one case: the diamond is not cut properly). 

  This method actually uses the principle of the refractive index of gemstones. The higher the refractive index, the harder it is to see through. Therefore, cz has a lower refractive index than diamond, so it is easier to see through than diamond. However, because this method is only suitable for round brilliant cut diamond, if the diamond is stained with liquid, it will be transparent, so I personally suggest that you cannot blindly believe this method, and you need to combine other methods.

 cz loose

  Third, lipophilicity test. We know that diamonds are lipophilic, especially when they are touched by hands, they look like they are covered with a oil film. So we can take advantage of this feature and use an oil-based pen to draw a brush on the clean diamond table. 

  If it is a diamond, there will be continuous line. If it is cz, there will be intermittent points. Of course, the lipophilicity test is not limited to this one. You can also place a small drop of liquid on the table to see if the droplets will spread out, but this test will have limitations and it is not recommended for individuals.


  Fourth, weight. This method uses the relative density of gemstones to distinguish diamond and cz loose. The relative density of diamond is 3.52, and the relative density of cz is 4.73. It means that the same volume of diamond and cz are weighed together, the heavier is cz and the lighter is diamond. I think this is sometimes inaccurate. It is better to use an instrument to observe it.


  The above four methods are the easiest to distinguish diamond and cz for consumers who do not know it. Of course, those who understand it better can combine the basic properties of diamond and cz for further distinction.

rd cz

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