How to Identify Real Gemstones from Fake Ones

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Go for Genuine Sparkle

Knock-off gemstones are everywhere these days. It is therefore important, as consumers, to learn the difference between real gems and fake ones. Here’s our handy guide to help you distinguish the real deal from the faux stuff.

Identifying Real Diamonds from Fake Ones

  • Real diamonds sparkle more because they have a higher refractive index.
  • Placing the diamond under a UV light will usually produce a blue fluorescence (faint or strong). Not all real diamonds exhibit this property, but most do.
  • When you blow warm air onto a diamond, the ‘fog’ will clear up in less than a second. Real diamonds are able to dissipate heat much faster than fake ones.
  • Real diamonds are not visible in an X-ray! Fake ones are!
  • When a fake diamond is heated for about 30 seconds and thrown into cold water, it usually shatters. Real diamonds don’t.

Identifying Real Rubies from Fake Ones

  1. A real ruby is significantly harder and denser than tourmalines and garnets which are often passed off as rubies.
  2. A real ruby will have a consistent dark red colour and clarity throughout and usually does not appear foggy.
  3. Larger rubies usually come in fancier shapes (pear, cushion etc.), so if you find a big ruby in a simple round shape, it is most likely fake.
  4. Real rubies, just like diamonds, don’t scratch easily, even when scratched with a knife or sandpaper!
Identifying Real Emeralds from Fake Ones

Real emeralds tend to have tiny inclusions inside which are visible when seen through a jeweller’s loupe or sometimes even to the naked eye.
Lab grown emeralds will have better colour and fewer internal flaws but will cost you a fraction of a real emerald. So if an emerald is being sold to you at throwaway prices, it’s most likely fake.

General Tips to Keep in Mind


The best way you can ensure that you’re buying real gemstones is to have the stone appraised by a professional jeweller. This usually costs money but it will give you peace of mind. You can also ask for a certificate attesting to the quality and price estimate of the gem from a reputed grading authority such as the European Gemological Laboratory or the Gemological Institute of America.

The beauty of real gemstones is in their slight imperfections. If your gemstone is “too perfect” or very smooth, it is likely to be a fake. Real gems are a little bit flawed, externally and/or internally and can often feel ‘rough’ or a little waxy. And always keep in mind the old adage, if something is too good to be true, it probably is!

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