How To Tell If A Diamond Is Real or Fake?

10 easy ways to distinguish between real and fake diamonds!

Got a diamond and now you are wondering if it is authentic? Read on to discover several ways to determine at home whether your diamond is real or a fake. You want your diamond to be natural, authentic, and untreated. This combination of characteristics is the recipe for the most valuable and beautiful diamonds with the most investment value and the most resale value.

Is it real or fake diamond ring?Is it real or fake diamond ring?

Before we go on, let’s review a little bit of diamond terminology so we can clarify this process for you. Diamonds can either be natural or synthetic, meaning that they were either mined from the ground or were grown artificially in a laboratory. Natural diamonds can also be chemically enhanced, meaning that a scientist chose to ‘clean up’ imperfections in the diamond via any of a means of methods in order to enhance the diamond’s appearance.

You want to determine that you have a diamond, not an alternative, i.e. a cubic zirconia, a white sapphire, a white topaz, or a moissanite. The following tests will largely determine that your diamond is a diamond and not an alternative stone, but they will not determine if it was grown in a laboratory or underwent any cosmetic work.


One of the easiest ways to determine the status of your diamond is by the price. If the price is too good to be to true, that is your warning sign. Genuine natural diamonds are never sold at steeply discounted prices, and the prices that are categorized as ‘rock bottom’ are still not cheap in any way. This test is probably only relevant if you are in the shopping prices and not if you are evaluating an heirloom, as chances are you do not know the price that was originally paid for the diamond, and even if you do, the prices have probably changed since then.

Bottom line = a real diamond is not cheap

GIA Certificate

Another easy way to tell if a diamond is real is if it has a genuine GIA certificate. Other laboratories do exist in the diamond world, but the GIA is by and large the most trustworthy independent grading laboratory in the world. If a diamond has been issued a grading certificate from the GIA, it has already gone professional evaluation and has been not only tested as to its authenticity but also quantified into its respective 4 C’s, the next step in the process. The GIA will never issue a grading certificate to an inauthentic diamond so you are guaranteed that if the diamond has a GIA certificate, it is real.

Bottom line = only a real diamond has an authentic GIA certificate

Setting Quality

The next at-home test involves a simple piece of equipment called a jeweler’s loupe. If you are unable to borrow one from your local jeweler, you can easily purchase a good inexpensive one on a website like eBay for little cost. With this loupe you can correctly inspect the setting of the diamond. If you see that it is set in gold or platinum (with any of the following stamps: 14K, 18K, 24K, 950, PT, Plat), then it is more likely that the stone is a real diamond. Fake diamonds are not usually set in such valuable metal.

Bottom line= Fake diamonds are usually set in cheap metal


Unless you paid an extremely high price for the diamond, chances are that there is some sort of imperfection in it. Only fake diamonds are completely flawless. If you look at the diamond under a loupe without its setting, you should be able to spot some sort of flaws inside the diamond. Depending on how flawed your diamond is on the clarity scale (Flawless, Internally Flawless, Very Very Slightly Included, Very Slightly Included, Slightly Included and Included), the diamond will have varying amount of flaws that will be visible under the 10X magnification of the loupe.

Bottom line= most diamonds are not completely flawless so look for flaws in your diamond with a loupe


Diamonds are the hardest and strongest substance on earth because of their geometrical composition. In fact, the only substance that can cause any harm to a diamond is another diamond. For example, when diamonds are discovered in their rough form, the only way that diamond polishers are able to polish them to their recognizable form is on a polishing wheel that is coated with diamond dust. The dust is what actually causes the wheel to have its desired effect. Therefore, if you want to test if a diamond is truly a diamond, rub a piece of sandpaper on its surface. If the sandpaper scratches up your diamond, it is not a diamond.

Bottom line= If a piece of sandpaper can scratch up your diamond, it is not a diamond.

X Ray

Another test that applies because of the unique properties of diamonds is the X-ray test. If the diamond shows up in the X-ray it is not real. If the diamond passes through the X-ray but does not show up, then it is real.

Bottom line= A diamond will not show up in an X-ray.


Another principle that tests diamonds is the fact that diamonds do not retain heat, which is because of the same reason as above – they are the hardest and strongest substance on earth. Therefore, another test on diamonds is the infamous fog test. Breathe onto your diamond as if you were breathing fog onto a mirror or window. If the fog stays, it is not a real diamond. If the fog does not stay, the diamond has passed the test.

Bottom line= A diamond will not fog up if you breathe onto it.


The following 3 tests can only be done on a diamond that is not already mounted into a setting. This test is directly related to the fog test because it is based on the same heat principle. If you heat up a diamond, the heat will not have any effect on it. Take the diamond and hold up a lighter next to it with the flame lit. If the diamond bursts, then it is not a real diamond. If the diamond is fine, then it is real.

Bottom line= A real diamond will not be affected if exposed to heat.


A diamond is composed of numerous facets that refract light in a way that causes them to be sparkly, what is known as brilliance, and incredibly beautiful. This same characteristic also causes them not to be transparent even though they seem to be. Therefore, if you can see through the diamond, it is not real. Set the diamond on a piece of newspaper. If you can see the text under the diamond, it is fake. If you cannot see it, the diamond is real.

Bottom line = A fake diamond is transparent and you can read the text of a newspaper if it is laid on one.

Density in Water

One of the characteristics of real diamonds is that they have a high density. Therefore, if a diamond is dropped in a glass of water, it will sink to the bottom. A fake diamond will float to the top of the glass.

Bottom line = A fake diamond will float on the top of a glass of water.

Of course, the best way to truly distinguish a real diamond from a fake one is with an experienced professional. There is specially developed equipment just for this purpose and if you give your diamond to a jeweler that you trust, you can be sure that they will test it for you and let you know its