2017-02-21 15:31:51 Writen By: Hatton By Design

Ways to Spot a Fake Diamond. No.3

No.3 The Fog test


At Hatton by Design you’ll never run the risk of buying a fake diamond! All of our diamonds are certified. Fact. But just in case you’re ever in any doubt, here’s a neat little trick...



Is my diamond real?

Here is a super-quick way to check the authenticity of a diamond...


heart on glass



First the science: a diamond is in fact a very efficient thermal conductor, or, in other words heat passes through it very quickly. Compared to copper, a diamond is actually five times more heat conductive. Gemmologists use this fact as one test to distinguish between real and fake diamonds by using apparatus to measure how quickly heat passes through the stone. Obviously not something you can do at home unless you have a spare thermal probe lying around! But, you can do a similar test by simply blowing onto your diamond.


So, take the diamond in question and blow on it, in much the same way as you blow on a window or mirror to fog it up. If it does get foggy then it’s not a real diamond, that is because the real thing will disperse the heat immediately. Other materials will take longer to conduct the heat and so the fog will remain for two or three seconds.


Dirt or grease can affect this test so make sure that you clean the diamond first!




Read my other articles in Real or Fake Diamond?: No.1. The Jeweller's Loupe, No. 2. The Sandpaper test

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