How to Test if a Diamond is Real or Fake


How to Tell if a Diamond Is Real or Fake


Did you just pull off an impressive heist? Or maybe you made a major black-market deal. Or maybe you just want to make sure the rock is real. In any circumstance, being able to tell if a diamond is authentic can be a specifically handy tool for some peace of mind to make sure you’re giving your love the real thing, or it can just be a nifty trick you can occasionally show off. Today we’ll teach you how to add this tool to your arsenal.

Test by a Jeweler

The first and by far the most accurate way to ensure a diamond is real is to get it tested by a professional. If you’ve already spent the money or are planning on dropping the dough, why not send the diamond to a jeweler to be sure you are getting what you’re paying for? They have advanced and precise tools that the average man doesn’t have around.

Test by Jeweler - Diamond

They’ll use finely tuned scales to test the weight, loupes to check for imperfections and light refractivity, test for electric conductivity, and other scientific methods to check the rock. They also have years of experience doing exactly these types of things. Don’t second guess it, take it to a professional to be absolutely sure.

If you do take it to a professional, also remember to have the diamond rated and certified. You will be able to always prove the diamond is real and you’ll know what it’s worth now and down the road. This information is always valuable.

But that’s not what this article is about. You want to know some tips and tricks to perform in your own abode. You want to feel like a scientist or an underground art dealer. The following tests will help you achieve just that.

Eye Test

They eye test is the one we all see in the movies. This is the classic and yet possibly the most difficult and inconclusive home test. A vast majority of humans will not be able to do this test with their naked eye as they just aren’t powerful enough, so you will need a magnifying glass or a loupe, which is the small little magnifying glass you see in all those movies.

Eye Test - Diamond

Hold it up to the diamond and examine it. You are looking for imperfections. All diamonds, no matter how sparkly and luminous they are, have small imperfections within them. The nicer the diamond, the fewer imperfections. But they all have them. So, if you see some marks within the diamond it could be real. If you see no imperfections, it probably is a fake.

But you may not have good enough eye either to spot them. Basically, don’t rely on this test unless you practice all the time. Try some of the others suggested here.

Fog Test

This is the fastest test presented in this article. And it’s very simple. Make sure the diamond is clean and free of finger oils and such, and simply breathe on it. It will fog up due to the heat. The dispersion of the fog is the test. If the fog goes away very quickly, within one or two seconds, the diamond is probably real. If it stays for longer than that, there’s a good chance it’s fake.

Diamonds are excellent heat conductors and thus disperse heat very rapidly. So, the heat creating the fog won’t last very long and the fog will disappear. Simple test, fairly conclusive, but not fool proof.

Floating test

Another simple test to perform, but not a very conclusive one. For this one you’ll want to go to the bathroom and drop the diamond into the toilet. If your diamond is real, it’s gone. Just kidding, very much so. Don’t use the toilet. Fill a glass with water and drop the diamond into that. Diamonds are very dense and will therefore sink to the bottom. If it floats, it is definitely a fake.

Floating Test - Diamond in Water

This test is only good to determine a fake, not an authentic diamond. Many fake diamonds out there are made very well and will also sink if put into water. So, don’t think the diamond is real if it sinks. Just know that it’s a fake if it floats.

Refraction Test

Real diamonds are excellent light refractors. This means light waves get bent as they pass through the diamond. The refraction makes it basically impossible to see straight through the diamond. There are a few ways to test this refractivity.

Refractor Test - Shining Diamond

The first is to use a newspaper. Place the diamond on the newspaper over a letter with the flat side down. Looking straight down through the pointed tip of the diamond, if you can read the letter, even if it somewhat blurry, the diamond is a fake.

The next is similar to the newspaper. You just make a dot on a blank piece of paper and place diamond flat side down on top of the diamond. Look down through the pointed end and if you see the dot, the diamond is fake.

The last only requires some light. Simply hold the diamond under a normal light and move it around. Are there brilliant sparkles and possibly different colors refracting off the diamond? if so, it’s probably a real diamond. The more sparkly, the nicer the diamond. This test can be difficult to use accurately without practice or without a fake diamond to compare it to, so don’t rely on it.

Also, these refraction tests should be treated similarly to the floating test. They can tell if a diamond is fake but not necessarily real, as fake diamonds these days can emulate a real diamond’s refractivity to the untrained eye.

Fire Test

Now we’re to the manly stuff. Some major badass chemistry. This test also isn’t for the irresponsible or faint of heart. As stated before, diamonds are excellent heat conductors. They were formed under extreme pressure and heat over many years. They can handle a little man-made fire.

Fire Test - Burning Diamond

For this test you’ll need a cold glass of water, some sort of lighter, and a way to safely hold the diamond without burning yourself or your house down. Use the lighter to heat the diamond for 30-40 seconds and then immediately drop the diamond into the cold glass of water. If it’s real, nothing will happen. If it’s fake, the diamond will shatter and break into several pieces.

This test takes some time and effort and safety, so only do it if you’re serious about testing the diamond and if you don’t want to lose the fake diamond. Be smart about it.

Ultraviolet Light Test

Ultraviolet Diamond Test

This test is more of a novelty or to know for sure if some diamonds are real. You simply hold the diamond under a black light and if it glows blue it’s a real diamond. If not, it still may be as only about a third of actual diamonds glow blue under a UV light. So, don’t rely on it. But if your rock does turn blue, you probably know it’s the real thing.

Scratch Test

This last test is last for a reason. It’s based on the old adage that diamonds are the hardest material on the planet. While this isn’t true, they are very hard, so much so they can even be used on blades to cut through hard metals and other materials.

For this test you’re supposed to attempt to scratch some glass or a mirror with the tip of the diamond. If the glass scratches, it could be a real diamond. Or not. Many fake diamonds made of cubic zirconia or moissanite can also be very hard and scratch the glass as well. Therefore, we don’t recommend this test. Plus, there’s always a chance you damage the real diamond in the process making this test all the more worthless.

Final Grade

Many of these tests are cool and handy in a pinch, but none of them are absolute. So, if you eliminate the possibility of a fake through some of these tests, take your diamond to a jeweler and have it tested for certainty. Then get it rated and certified and be happy that the rock is real and show the love of your life your dedication through consumerism! Just kidding, diamonds are a great gift. Just always be sure you’re getting what you pay for, gents.