This guide is useful and practical yet no single at-home test should be regarded as conclusive. A diamond expert has the proper experience and equipment to confirm if a diamond is real or fake. Contact us for premium quality authentic diamonds or Browse our mega collection here.
This advice is for people who own diamond pieces or collections and want to know if they are real. This guide will provide you with at-home tests along with tests a diamond expert or jeweler can conduct with specialized equipment.
If you’re not familiar with a diamond’s structure and components, you may be led to think that a gemstone is a diamond when it’s an entirely different stone—like cubic zirconia or moissanite. For this reason it’s essential to know how to spot a fake diamond.
Diamond Test #1 – Drop in Water
The water test is one of the simplest ways to spot fake diamonds. But this will only work if your diamond is loose.
Get a drinking glass and fill it with clean water. Carefully drop the loose gemstone into the glass. If it sinks, it is a real diamond. If it floats underneath or at the surface of the water, you deal with a fake diamond.
Although this test might seem to be quite simple, it is based on gemstone’s density level. Real diamonds are incredibly dense (3.51 g/cm³) and usually outmatch the fakes in density test. However, keep in mind that good-cut cubic zirconia or glass is actually pretty heavy and could pass the water test as well.
Diamond Test # 2 – Breathe on it
The Breathe or the Fog test is another easy method to tell a fake diamond from the real.
Position the stone close to your mouth and breathe onto the flat surface of the diamond. Imagine you are breathing into a mirror to make it foggy. Diamonds immediately dispense heat, so instead of remaining cloudy, the diamond would become instantly transparent.
Try this same test on cubic zirconia. The surface of the CZ will continue to be foggy. This test will help you determine if you have a CZ instead of a diamond, but the test will not tell the difference between moissanite and diamond.
Diamond Test # 3 – Read Newspaper Through It
The newspaper test works well when you have a slightly larger stone. Take the stone and place it flat side down onto a page of a newspaper or any other paper with lots of lettering. If you can read the letters, even if the letters are blurry, the diamond is fake.
If you place cubic zirconia over a piece of a finely printed newspaper, you should be able to read the print underneath the stone.
Diamond, however, refracts the light in such a way that you cannot read the print below it. If you don’t have a piece of newspaper lying around, take a piece of paper and draw a small dot on it. You will not be able to see the dot through a real diamond. However, if the diamond has an irregulat cut, this test won’t be reliable.
Diamond Test # 4 – Notice its Sparkle
The sparkle test is just plain looking at your stone in the light. So to do this test take the diamond and hold it under a normal lamp and observe carefully.
A real diamond reflects light extremely well, providing bright shimmers of white light and colourful light reflections. A fake diamond such as Cubic Zirconia sparkles with more dazzling colours, while an authentic diamond reflects light in a more “elegant” way. So if your stone sparkles in many colours, it is probably fake.
This guide is useful and practical yet no single at-home test should be regarded as conclusive. A diamond expert has the proper experience and equipment to confirm if a diamond is real or fake.
Expert Techniques
While at-home tests are fun and cost nothing, it is recommended to bring the stone in question to a diamond expert to a definitive answer on its authenticity.
Using a Loupe or a Microscope
Diamond professionals use a special magnifying glass or a microscope to inspect diamonds and other gemstones. Under magnification, an expert will look for blemishes and imperfections within the stone.
While a fake diamond can be perfectly flawless, a real gem will have small imperfections even though they are not visible to the naked eye. So if the stone is too perfect, most likely it is not a real diamond.
Using a Diamond Tester
A diamond tester is a special tool used to indicate whether a stone is a real diamond based on its physical properties.
The principle of its operation is based on the fact that different gemstones have different chemical structure and thus they conduct heat and electricity differently. Meaning, heat or electricity will pass through a diamond in a different way than it would through Cubic Zirconia, for example.
It’s important to mention that the tester that measures only thermal conductivity cannot tell a real diamond from moissanites as these two stones are very similar when it comes to interaction with heat. The diamond testers that measure electrical conductivity are more accurate in such a case.
