If you’re not that familiar with diamonds, you could be led to think that a simple gemstone is a diamond when it isn’t. So, here is our guide to spotting a fake diamond from an authentic one:

The Water Test


This is a simple test to tell you whether or not a diamond is authentic. Find a drinking glass and fill it three-quarters of the way with water. Drop the loose stone carefully into the water. If the stone sinks, it’s a real diamond. That’s because diamonds have a high density.

Inspect a diamond using a loupe


Check out the diamonds for sale at The Diamond Jewellery Studio. At such reliable jewelers, you can look through a loupe, which is a special magnifying glass used for gemstones and jewellery. You can use the loupe to look for imperfections and blemishes within the diamond. Diamonds tend to have small inclusions or imperfections.

The Fog Test


For this one, hold the stone between two of your fingers and breathe on the stone. A light fog should form on the diamond from the heat and moisture of your breath. If the fog disappears immediately, the diamond is genuine. If it takes a few seconds, you’re dealing with a fake.

Mount and Setting


If the diamond is already set in a ring, take a good look at the mount and setting. Because of a diamond’s hefty price tag, a real one will be set in high-quality jewellery, such as platinum or white gold and may have a side-stone or halo setting.

Using a UV Light


For a different kind of way to test a diamond, place it under a UV light and see what happens. Authentic diamonds tend to emit a blue glow and others may not glow at all. Keep in mind this isn’t a particularly definitive test and you may need to use some of the other methods, too.

Use Refractory


When you see a diamond sparkle, that is its ability to refract light. When light strikes the angled surfaces on the lower portion of a diamond, it bounces and refracts up through the top, flat part of the diamond’s surface. When a diamond does this and sparkles radiantly, it is referred to as brilliance.

Other stones like Cubic Zirconia do not refract light as well and have less brilliance.

The Dot Test


On a flat surface, place a white piece of paper and draw a small dot with a pen. Then, lay the stone on the dot, flat side down. Look through the pointed end of the stone, down onto the paper. If you notice a circular reflection within the stone, it is likely a fake. If you can’t see the reflection or dot in the stone, it’s an authentic diamond.

A genuine diamond has a powerful refractive quality, so light tends to bounce in different directions rather than a straight line. This is why you cannot see the dots or letters through a real diamond.



Use these simple tests to determine whether or not a diamond is authentic!