How To Identify Real Diamonds

With diamonds being the most sought after stones in the world, it goes without saying that a lot of shady frausters try to pass off imitation diamonds as the real thing. In the movies you may have seen someone test a diamond by trying to scratch glass with it. It is true that diamonds can scratch glass, but so can many fake diamonds, so this should not be seen as a reliable test.  So in order to avoid being scammed and to make sure your investment is genuine, I'll introduce you to some ways to spot fake diamond sepcimens and identify real diamonds.
Of course, the most reliable method is to take the diamond to  a reputable jeweler for a third party appraisal.  This may be practical if you are interested in purchasing one specific diamond, so not so if you are interested in a variety of possible purchases. The seller may also produce a certificate from a reputable third party diamond grading authority.

 When inspecting a diamond yourself, one way to test its authenticity is to look through it. Diamonds are highly refractive and bend light to a large extent.
So when you look through the diamond you shouldn't be able to see through it from top to bottom. One way to test this is to place the stone on a piece of
newspaper. If you can see the print, then it probably is a fake diamond. Similarly, if the diamond is mounted, looking from the top of the diamond you
shouldn't be able to see through to the bottom of the diamond.
Another way to check if the diamond is real is to look at its reflections. True diamonds' reflections appear in gray, so if you see see rainbow spectrum reflections, it is most likely a fake.

Diamond testing: real, fake?

You could also test the stone under a UV light. Real diamonds will often have a blue fluorescent hue under ultra violet light, while an absence of blue likely means it is fake. It should be noted however that while the presence of blue confirms authenticity, the absence of blue does not confirm that it is fake.
Another common way to check the stone is to weigh it. Diamonds are much lighter than Cubic zirconia of the same shape and size. Comparison charts can be found online here.
One last way to test the stone is to drop it in water. Many con-artists cap fake diamonds with a diamond exterior, but when submerged in water the cap is much more visible and you will likely spot that the interior is not real diamond.
There are other ways to test to identify real diamonds, but they often require special equipment that normally belongs to professionals. These methods are intended to help you and prevent you from being conned. But they are intended to supplement professional appraisal, not replace it. Please take all necessary precautions when buying a diamond, an important purchase that requires due diligence.