How to Tell if a Diamond is Real

Aside from buying a house or car, spending the big bucks on a purchase doesn’t happen every day. We’re talking about putting down a significant chunk of your savings or taking out a loan that will take years to pay off. Engagements, anniversaries, and important birthdays have been celebrated with diamonds throughout history, and those traditions are still going strong. And that chunk of stone is going to cost you a hefty chunk of cash. 

But there’s always one question itching at the back of our mind when we lay eyes on a diamond for the first time: is that thing real?

Today we’re going to equip you with some knowledge and tools that will help you answer that question and fast.

Easy At-Home Tests To Try

Before you load up your entire diamond collection and take it to the shop downtown for a professional inspection, you can run a few authenticity tests in your own home, with pretty accurate results.

If for some reason, you’ve got loose diamonds lying around, they will be easier to test. Maybe you’ve inherited gems from someone who recently died, or you’ve invested in a grab bag of stones from a retailer going out of business. Loose diamonds aren’t uncommon, and there are some quick ways to verify they’re real.

The first technique only needs a glass of water from the sink. Drop your diamond in the water, and watch it either sink to the bottom or float to the top. If your stone sinks, it’s probably a diamond. If not, tough luck – it’s likely asimulant like CZ or Moissanite.

This test won’t definitively prove you’ve got a genuine diamond, but it will weed out the fakes.

You can also heat up the suspicious stone with a lighter before dropping it in water for a real make-or-break test – it will shatter in the cold liquid if it isn’t real. Rapid expansion and contraction from heat and cold will do nothing to a real diamond. Obviously, don’t do this if you’re interested in keeping your stone or jewelry, even if it is fake. 

A Closer Look

If you have good eyesight, you can look for some telltale signs that a diamond is no joke.Refractionis the keyword here, and you want to look at how the light passes through the stone and detect sharp bends and redirections.

The brilliance of a stone will distort any text or pictures on the other side of it. Hold it up in front of a piece of newspaper, and you won’t be able to read a word because the diamond will distort the letters.

You can run the same test by drawing a black dot on a white piece of paper. If you’ve got a real diamond, that dot will look clear and non-distorted when you look directly down through it.

With some practice, you can discern the degree of refractivity faster and with fewer tests. Look for these classic clues that your diamond is for real:

  • Rather than trying to count the number of angles and reflections within the stone, check for the amount and intensity of sparkles present in the piece. Compare it to a chunk of glass or quartz to see the variance in brilliance and complexity.
  • Simulant diamonds look real and often have that blinding, sparkling shine you get from the genuine article. In some cases, extreme “fire” may be a giveaway.
  • By sparkle, we mean theintensity of the light refracted, not pretty colors. If you’re seeing rainbows, you’re probably dealing with moissanite, not diamond.

The lesson to take away here is that real diamonds are in the sweet spot between overly shiny, too colorful, and refractive. They will never have a blurry, greasy, or “iced-over” look.

Take It To The Pros

As we said, it takes tons of study and practice to figure out a diamond’s authenticity on sight, so don’t get frustrated if you can’t do it – that’s the whole point of licensed professionals.

If you’ve tried all the at-home tricks and you’re still scratching your head about the gems in your hand, it’s time to get them looked at more closely.

Almost any commercial jeweler or department store hub will inspect your wares without asking for a dime, and you will likely get the answer on the spot. Here are a few ways they do it.

The heat probe test requires a special piece of machinery that most jewelers will have. The tool is used to heat up the stone at a single point of contact and gauge how long it retains that elevated temperature.

Diamonds disperse heat fast due to their unique crystalline structure, so a stone that holds onto the heat is likely something else. This test can be done in under a minute and will typically give you a definitive answer. Plus, it won’t damage the stone.

An electrical conductivity test will reveal even more information about your stone, telling you whether it’s moissanite or genuine diamond. Combination tools are found in most shops, but you can also purchase one yourself if you’ve got a bunch of stones to test.

Other tests get into the nitty-gritty of the stone’s structure, involving microscopic examination or inspection under ultraviolet light. If you notice a flash of orange color under the scope, you’ve likely got a stone composed of Cubic Zirconia.

Under UV light, you’re looking for a blue glow from your stone, which indicates its status as a diamond. This test isn’t 100% foolproof, but it can help the jeweler narrow things down.

The pros may weigh your stone alongside a diamond of near-identical size to figure out the truth. Cubic zirconia, for instance, weighs 55% more than a real diamond, so this test can be a dead giveaway if nothing else works.

Finally, there’s the x-ray test, which will tell all. Diamonds do not appear in x-ray scans due to their radiolucent molecular structure, and this might bethe last test you need. If nothing else works, send the stone to a lab to get the x-ray you need.

Register For Authenticity

If your diamond passes all the tests and you make a great discovery, congrats. Take that stone to a diamond appraiser to make it official.

An appraiser will check out your diamond and give it an estimated value. Best case scenario, you’ll seek the services of someone NOT involved in the sale of diamonds, so they have an unbiased opinion on the value of the stone.

Also, try to find an independent appraiser with credentials from a Gemological Institute like the GIA. They’ll be more trustworthy, which could end up saving you time in the long run. Watch how the appraiser works during the process, ask plenty of questions, and you’ll probably learn some interesting facts along the way.

At the end of the session, request a certificate of appraisal and keep that sheet within close reach for as long as you own the stone. This paperwork will include the key details of your gem that you’ll want to know if it ever comes time to sell.

Have A Great Jeweler On Your Side

Whether your diamonds turn out to be natural or man-made, hopefully, you won’t be shocked to discover the truth. It could either be a nice surprise, a breath of relief, or a nightmare, depending on the outcome.

In the future, you want to test more gems with professional gear, or you just want a reliable source of genuine or synthetic diamonds to fill out your collection. Any way you cut it, you’ll want to have a trusted jeweler on call, ready to give advice, answer questions, or clear up any uncertainties about past or future purchases.

When it comes to jewelry, there’s no such thing as being too informed, even in the era of the internet. A trusted company can be a huge asset as you build your knowledge base and expand into new territory.

Discovering new jewelry is about finding what you love, but a great jeweler like 6 Ice can seriously help point you in the right direction from the start.

If real diamonds are out of your budget at the moment, you can still enjoy big, bold pieces with synthetic stones like CZ or Moissanite, the main materials we discussed earlier.

Considering that it isn’t so easy to determine the verity of these stones on sight, these pieces will deliver their desired effect and enhance your style without breaking the bank.

Today’s synthetics look great and last a long time with the right care. Take a risk and try out something new.


There are countlessways to test diamonds for verity, some more effective than others. Try out some home solutions or take them in for professional treatment if you’re stumped. No matter what you discover, enjoy those gorgeous gems regardless.