8 Quick and Easy Ways to Tell if a Diamond is Real or Fake

By Frank

Highly experienced diamond polisher who loves to share his knowledge with you. Continues to stun his colleagues with interesting - or simply bizarre - facts about diamonds and gems.

March 14, 2017

Are you wondering whether your boyfriend, fiancé or husband bought you a real diamond ring or a fake one? Or have you been in business with a shady diamond trader? As a professional diamond worker, I give you some easy tests you can do at home to check whether your diamond is real or fake.

Apart from your renowned jewelers, there are a lot of sinister “diamond businesses” out there. Not only do they try to sell you a diamond of bad quality. Sometimes they try to sell a diamond that is not even real at all. If a bargain sounds too good to be true, you better make sure you’re talking about the real thing here. Luckily, there are a few quick and easy tests to find out if a diamond is real or fake. You can do these tests at home and some even on the spot.

Diamond cutter evaluating if diamond ring is real or fake

Test 1: Search for impurities

99.9 percent of the diamonds are not pure; they have small imperfections. The fake diamonds are generally perfect. If you got a flawless stone, you’re either dealing with one the 0.01% perfect diamonds, or you got a fake one.

Necessities:
Magnifying glass or loupe, preferably 10x magnifying

Level of difficulty:
Quite hard

Accuracy:
4/5

How do I search for imperfections in a diamond?

Examine the diamond with an as enlarging lens as possible, preferably 10 times enlarging. Search for small black spots, air bubbles or tiny fractures. Know what you are looking for and don’t confuse ‘scratches’ for impurities. This is because a real diamond doesn’t get scratched easily. Can’ find any impurities? I’m afraid I’ve some bad news for you then…

Keep in mind however that using a loupe correctly is very difficult for the untrained eye.
> Find out if you’re using the loupe correctly

checking if facets of emerald cut diamond are real

Test 2: Examine the facets

Look at the facets that the diamond has been cut in. It’s way easier to check the facets rather than look for impurities

Necessities:
Magnifying glass or loupe, preferably 10x magnifying

Difficulty:
Medium

Accuracy:
4/5

How do I examine the facets of a diamond?

Real diamonds have sharp edges because they are cut by professional diamond cutters. Fake diamonds are often created by molds to melt the glass or zircon in. When molds are used, the “diamond” will not have sharp edges, but round ones. However, it is possible that a zircon or a piece of glass is cut like a diamond. In that case it will have sharp edges, even though it is not a real diamond.

Gold ring with hallmark inside as a proof of real gold and diamonds

Test 3: Look at the metal

The kind of metal the diamond is mounted on, can tell you a lot.

Necessities:
None

Level of difficulty:
Easy

Accuracy:
2,5/5

Where do I look for when checking the hallmark in the metal of a diamond ring?

Even though it is not a foolproof test, it is super easy. Since diamonds are expensive, they are often set in more luxurious and expensive material. If the metal is silver or gold plated, you can, therefore, be quite sure the diamond is fake. Real diamonds are normally set in white, yellow or rose gold or in platinum rings.

craftsmanship is often a sign of real diamond

Test 4: Evaluate the setting and craftsmanship

A real diamond polisher and goldsmith take pride in their job.

Necessities:
None

Level of difficulty:
Fairly easy

Accuracy:
3/5

How do I evaluate the setting of a diamond ring?

This test is basically an addition to the previous one. If the setting is of poor quality or if the craftsmanship is poorly done, the diamond is probably fake. A real diamond worker makes sure the diamond is carefully placed because he takes pride in his work. The overall impression of the ring is therefore perfect.

Sandpapering to check if diamond is real or fake

Test 5: Sandpaper the diamond

Sandpapering the stone is only a good idea if you’re sure you have a real diamond or if you don’t mind losing a fake one.

Necessities:
Sandpaper

Level of difficulty:
Easy

Accuracy:
4/5

How should I sandpaper the diamond?

This one is for the risk-takers. Make absolutely sure you use regular sandpaper and not one that is covered with diamond powder. As you might know, a diamond is extremely hard; sandpaper won’t damage it. If you sandpaper an unreal diamond though, the stone will be scratched. Only use this method if you don’t mind damaging a fake diamond.

Woman breathing warm air on a diamond to test if real or fake

Test 6: Breathe on the diamond

Do you know how to make a window foggy by using your breath? Let’s see if we can get your diamond fogged up.

Necessities:
None

Level of difficulty:
Easy

Accuracy:
3/5

How do I fog a diamond?

Breathe on a diamond with warm breath, just like you would do on a window to create fog on it. A fake diamond is going to be covered in fog for a short time; a real diamond will not get foggy. A real diamond does not retain the heat of your breath. The difficulty in this test is mainly related to the size of the diamond. For small diamonds, it is harder to decide whether they are fogged up or not. If possible, try the same trick with a stone you know it’s fake. If both “diamonds” fog the same, you know they’re both not real.

Keeping a diamond in natural light

Test 7: Watch the rainbow

The way a diamond reflects light is unique. Keep a diamond in the light and see the glare.

Necessities:
Natural light

Level of difficulty:
Medium

Accuracy:
4/5

How do I find the diamond rainbow?

As you may know, a diamond can create a rainbow on any surface when it reflects light. Within the stone, the light reflects gray and white. Outside the stone, you will see the rainbow colors. While stones that glare with the prism effect and let the rainbow colors show also inside the stone are usually fake. The difficulty in this test is that some fake diamonds shine even brighter than a real one. A moissanite for example.

see letters through a stone is a sign of a fake diamond

Test 8: Read the news

If you can read the newspaper, I’m afraid it’s bad news.

Necessities:
A newspaper

Level of difficulty:
Easy

Accuracy:
4/5

How do I use a newspaper to test a diamond?

Unfortunately, this test is only usable for loose (unset) diamonds. Look at the reflection of the stone. Place the diamond on a newspaper and if you cannot see the letters through the diamond, it is a real one. This is because the diamond bends the light in a different way. A fake diamond shows the letters and the whole newspaper through the stone.

The best way to tell if a diamond is real

At-home-tests are pretty accurate when it comes to checking if a diamond is real. But it’s almost impossible to be 100% certain. If you want to know for sure whether the stone on your finger is a real or fake diamond, please drop by. You can also take a free guided tour through our diamond factory. Because our diamond experts will gladly check the diamond for you. They can tell you if your diamond is real or fake.

But there is also a way to learn how to tell if a diamond is real by yourself. Just sign up for a Diamond Masterclass. Our master diamond polishers teach you everything there is to know about the craft of diamond cutting, including diamond evaluation. After the masterclass, you can stun your friends and family. You’ll be able to tell them who has a real diamond and who’s diamond is not…

Book a Masterclass

If you want to learn everything about the craft of diamond polishing and polish a diamond yourself as well, the Diamond Masterclass is the perfect experience for you.

BOOK MASTERCLASS

Contact a Consultant

Our diamond consultants are standing by to help you find that specific diamond piece you're looking for. They take all your wishes into account, including your budget.

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