How to Spot Fake Diamonds

Fake Diamonds can be found in Jewelry stores and in the gemstone trade. Most are small melee sized stones but occasionally they can be larger in size. If you do not know how to correctly identify fake Diamonds it can end up costing you thousands of dollars.

This guide is aimed at people who have Diamonds at home that are set or unset. The tests below are not definitive and if you have concerns about the authenticity of your Diamond it should always be tested by a professional gemologist. Another way to test your Diamond is with a Diamond tester like the one found on Amazon.

How to spot fake diamonds

By now we all know that diamonds can cut glass, but did you know that several other minerals also have that capability?  According to the standard Mohs Hardness Scale minerals from the hardness scale of 7, like quartz, to hardness scale 10, diamond,  are all capable of cutting or at least scoring glass. The glass scratch theory then, while an old standard is really not the best method in determining whether or not you have in your possession a diamond or Cubic Zirconia. Both of which can inflict scratches to glass without themselves being damaged.

How to spot fake diamonds

So, then, what are the best methods for spotting the real from the fake?  The web abounds with sites describing the various techniques and we’ve seen as many as 19 specific tests and as few as 5.  But really, there are a few basic methods that the lay-person can use and the glass scratch approach is one of them, although it isn’t necessarily recommended.

Test For Fake Diamonds At Home

  • Use a Loupe. A Loupe is a monocle-like magnifier and is relatively inexpensive. You will see most reputable jewelers using them.  The magnification allows for the analyst to determine for clarity and quality in the gemstone.  You may want to talk to a gemologist on exactly what you need to be looking for.  Having some comparisons nearby will be very helpful
  • The Fog Test. The fog test is really nothing more than cupping your hands around the stone and blowing on it.  Then you wait to see how long the condensation takes to evaporate.  Diamonds and other hard minerals tend to be excellent conductors of heat so quick evaporation is a good indication that you have a very hard material in your hand but, again, it is by no means definitive.
  • Use Heat and Ice. If you have a loose stone and you are brave enough then fill a glass with water and ice, pick up your rock with a tweezers and heat on a stove or with a lighter for roughly a minute or so.  Once the time is up, drop the heated stone into the ice water.  If it doesn’t shatter to pieces then you have a hard stone which may, or may not be a diamond.

How to spot fake diamonds

Tests Using Light

  • The Newspaper Test. Also known as the ‘Pen and Ink’ test, this very simple process will let you know quickly if you have a fake on your hands.  Placing the largest flat side down on newsprint or a magazine article, see if you can read the lettering.  If you can then you probably have a fake due to the way that diamonds refract
  • The Dot tets. Similar to the newspaper test, mark a piece of paper with a black dot. Place the Diamond with the flat side down and observe the dot through the point end of the Diamond. If you can see the dot, then it is likely a fake Diamond.

Tests Using Equipment

  • UV Light test. If you have a UV light or a black light at home you can observe the way the Diamond reacts under UV light. Most Diamonds will fluoresce with a blueish color and this is a very good indication of a natural Diamond. However if the Diamond does not fluoresce it does not mean the Diamond is a fake.
  • Diamond tester. Diamond testers are an easy way to test for the authenticity of a Diamond. Simply place the probe on the stone and look at the reading. These probes are very good at detecting fake Diamonds like Moissanite but they will not be able to tell the difference between a natural Diamond and a synthetic Diamond.

There are plenty of fun and informative and interesting sites available and all the ones we have looked at offer genuine advice on what to look for and they also say what we say here.  Please consult a professional if you have any concerns, your peace of mind is worth it!




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