Best Tests to Spot a Fake Diamond – How To Spot a Fake Diamond

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Diamond is considered as one of the most prominent jewelry out there. People often use this gem as a token of love, affection, and appreciation by gifting them as jewelry. When you are buying something as prestigious and delicate as this which comes at a great monetary expense for a stone, of course you would like to test its authentication.

There are many counterparts (Fake) out there which you will mistake for diamond. Several substitutes in the market resemble a diamond, and you would want to differentiate the original from them.

It would be helpful for you to know how to detect fake diamonds from the replicas or diamond look-alike gems, whether it is for a purchase or to inspect a jewel that you already own.

There are gems such as colorless zircon, moissanite, white sapphire, quartz, White Topaz, and many more which resemble diamonds, not by just looks; but also have many physical and chemical properties similar with them, making it harder to confirm its difference from diamonds.

How to Detect a Fake Diamond

The number of options to replace a diamond with a fake is alarming for you as a customer. Thus, you must know tips about checking the diamond’s authenticity first-hand.

You should also know that there are even artificial diamond look-like gems being created in labs. For example- GGG (gadolinium gallium garnet), YAG (yttrium aluminum garnet), and CZ (synthetic cubic zirconia). These items mentioned above are almost undetectable to any average person who does not have expertise in diamonds and gems.

Some of these replicants are not even completely worthless. They even have their worth with whatever value they might bring, even if lesser than a diamond. But know this, some qualities are unique to diamonds and cannot be faked.

The diamonds are certified by GIA, AGS, and IGI as top grades for authenticity. Before you go to any further depth, you should know the difference between a mounted and a loose diamond. It is easier to tell whether a diamond is real or not if it is not mounted.

To know if the diamond is real, you need to determine the flaws in it. A diamond that has not been mounted in a set yet, is easier to check. When purchasing a mounted diamond, you can ask your jeweler to remove the stone for a further thorough inspection.

It will become much easier to check for cracks or hidden flaws once the stone is removed from the setting. Mountings may sometimes reflect lights from within, making it difficult for average eyes to assess its color.

Best Tests to Spot a Fake Diamond

Top Ways to Find Out If Your Diamond Is Real or Fake

It is already evident that you can make many stones appear like diamonds with laser drillings or altering them in many ways. Diamonds are one of the toughest things in existence, so very hard to replicate. Even if the fake almost looks the same as diamond, there are properties that they cannot fake; this makes it reliable to test for whether it is real or not.

1. Test Your Diamond with Fog

This is one of the easiest and basic tests for figuring out a diamond. You do not need any tools for this test, just yourself. Take the diamond in front of your mouth, and then breathe on it. After that, wait for the fog to clear up.

It should not take more than two or three seconds for the fog to clear up if the diamond is real. If it takes more than 3 seconds to clear up or stays fogged for longer then there is a high chance you are dealing with a fake.

It is almost impossible to fog up a diamond. The condensation does not stick to the surface of the diamond for long, this is because diamonds can disperse heat instantly. It is in their nature, but even this test can be inaccurate sometimes.

The humidity and temperature of the room can also alter the result for how long the diamond will stay fogged. To know the set amount of time which a diamond will stay fog up in that atmosphere, you can compare it with another diamond. Run a test on the diamond that you already know is real before you do this test, to apprehend the amount of time it takes for fog to clear up in that room.

When doing this test, make sure the diamond is clean from any kind of dirt or oil. Otherwise, you won’t get an accurate result. This test works like a thermal conductor for testing diamonds, as they do not fog up but other imitation does.

2. Test Your Diamond with Water

Another one of the simplest ways to test your Diamond! You will just need a glass of water and a loose diamond for this test, nothing else. Get the glass filled with water, no matter what water you use. Then you drop that stone into the water.

After dropping the loose diamond into the water, the stone should sink to the bottom very quickly. Inspect how long it takes or how quickly that stone hits the bottom. This is because if it is an imitation, it is supposed to sink more slowly than a diamond.

If the gem does not sink immediately or floats on the water, then that stone is very likely to an imitation. This is because diamonds have a high density that allows them to drown very quickly.

However, not all fake diamonds are likely to float on the water. There are other imitations such as cubic zirconia, that may also sink very quickly. It would be better if you do not depend on only one test if you want to eliminate any doubts that you may have.

3. Use a Blacklight to Test Your Diamond

To run this test, you will need a light that can emit Ultra Violet rays. Make your room dark first, turning off the lights before running this test. Put the diamond under the UV ray when you are ready, then check for the fluorescence.

The blacklight will make your gem shine differently by giving off a fluorescence, inspect that light to know whether it is a diamond. If your gem is a diamond indeed, then it should glow blue under the light. If you do not see a blue color or see other colors like grey, slightly yellow, or green, then there is a high chance it is not a diamond.

Although most diamonds are likely to give a medium blue-like color when holding under a black light, some diamonds do not glow under UV light. Some diamonds may fluoresce yellow color or some are unreactive under the blacklight, same as imitations; so it makes it hard to follow.

When gems do not react under ultraviolet light, high chance it is not a diamond but there is also a slight chance that it could be a diamond. Do not conclude just after doing one test. Not all diamonds necessarily reveal a blue fluorescence. Visit a diamond expert, they can use their advanced equipment to make sure.

4. Perform Scratch Test on the Diamond

Another test that used to be practiced in earlier days for checking diamonds. It would be better if you use a loose gemstone for this test. It is common knowledge that diamond is a very extremely strong material. Here, the use of hard-known materials is going to be applied for the test.

Beware that, this process may be destructive. If the gem is not diamond, it may end up being damaged. If you want to keep the gem as it is, looking nice, and smooth, I suggest you do not go through this test.

You have to use the gem to make a small scratch on the material you are testing with. For example- scratch the loose gem on a mirror, see if it can put a scratch on the mirror. Not just mirrors, this test can be put to other materials as well, such as quartz crystal, or low-grade sapphire.

However, this test does not give accurate results. Meaning, there can be still a chance for the gem not to be a diamond. This is because even if it put a scratch on the material you were testing with, the gem itself might be harder than that material; not necessarily a diamond.

It could be moissanite or white sapphire that can put a scratch on the mirror. It would be better if you try to put in other techniques to the test; testing with a loupe is a better option and more accurate than a scratch test.

5. Test Diamond Transparency

This test is very appropriate for loose gems, not the set ones. You will need a newspaper with lots of lettering in it, or maybe small dots drawn in it. Then put the gem in a face-down position on the newspaper, try reading the letters or see through it.

If you can see through the letters or understand it, then you will know the diamond is fake. Because a real diamond will refract the light in many directions, you won’t be able to see through properly. A real diamond will bend the light intensely, so the letter will be unrecognizable. If it is a dot, you might not even see it at all!

Before proceeding with this test, make sure there is a sufficient amount of light. The light should be bright and no shadow must casted upon the diamond from any object. Diamond does not let you see through a straight line, always remember it refracts. They should not even appear wavy or distorted if it is a diamond.

How to Detect a Fake Diamond

6. Test with Your Diamond’s Weight

Measuring the weight of your gem is a good way to know whether the gem is genuinely diamond or not. First, you will need access to a scale for measuring the weight. This is something that you may not own, but you will find it in a jeweler’s shop for use.

First measure the weight of a real diamond that has the same shape and size as your gem, note it down. Then you can compare that report with your gem after you measure it. Most imitations will weigh more than a read diamond.

You will need a loose gem for this test. There is also a weight chart for diamond sizes. Measure the diamond’s breadth and width for matching with the chart’s weight to see if it is appropriate. This may not give you an accurate measurement if you make the measurement roughly with just a scale.

Also, there are other stones like Topaz, moissanite, spinel which have almost similar density with diamond; so there you go more risk of going wrong with a chart. The imitations could be heavier or lighter, measure their weights in a unit, Carats.

7. Check for Metal Markings

For this procedure, you will need a loupe and a pair of good eyes! Look for markings in the jewelry metal. They will indicate what type of gem has been mounted on this particular jewelry. The stone could be set on white gold, rose gold. Or platinum.

8. Use a Loupe

A Loupe is one of the most important tools when it comes to examining gems. It’s a small device for magnification, used on jewels to inspect them up close. Jewelers and experts prefer a loupe very much for their work.

Diamonds are bound to have some imperfections in them, which justifies they are real. Check for flecks or color changes in the diamond through the loupe. If you see any signs of flecks or color changing, then it is a high chance that the diamond is real.

When using the loupe, check at the edges of the gems to spot whether the facets are rounded, abraded, or chipped. Diamonds do not have rounded edges. You will be able to identify a fake if you take a closer look with the loupe. But keep in mind, imitations can also be made to have sharp facet edges.

There are many things to look into carefully with a loupe, and you need to be patient about that. Diamonds are most likely to have imperfections and blemishes, so that is a good cue. If you look closely, you should be seeing multiple angles in the crown facet.

See if the facets are doubling or not. If it is doubling then it may be an imitation, because diamonds refract singly. Gems like moissanite, white zircon, white spinel, topaz, quartz, and sapphire are mostly doubly refractive.

To avoid mistakes for dirt as imperfection, make sure the gem is clean before you inspect. See if there are any dark or light spots in the gem. If you happen to find tiny crystal-like bubbles in the gem, then it is an imitation.

This is because cubic zirconia and glasses have such bubbles in them, real diamonds don’t. Real diamonds have such qualities, that they all cannot be faked.

9. Use Heat to Test Your Diamond

Beware! If you want to keep the gemstone intact even if it is fake, then do not proceed on with this test. The test can ruin the jewelry setting for good.

You will need a lighter and a glass of cold water for this test. First, you need to heat the gem for 30 to 40 seconds. Then after that, immediately drop the gem into the cold water. The gem will shatter to pieces if it is fake.

Diamonds are formed under intense pressure and heat which allows them to endure such sudden changes in temperature. They are unaffected by this because they took billions of years to form under pressure.

By doing this, the gem first expands and then contracts right after when it is dropped into the cold water. Weaker materials cannot handle this process. However, gems like white topaz, moissanite, or GGG may endure such tests. Some moissanite even change colors when heated. Moissanite can turn green, brown, or yellow.

Make sure to take safety precautions before doing this test, because is fire play involved after all. You can use pliers to hold the gem when heating and use heat-resistant gloves.

10. Observe the Sparkle of Your Diamond

This is one of the simplest tests on this list. You do not require any extra apparatus for this, and only a good set of eyes. Hold the gem under bright light, it could be a lamp as long as bright. Observe the gem on how it sparkle.

You need to know how real diamonds sparkle and how it is apart from a fake. Carefully observe the bright light shimmering from the diamond. A real diamond is supposed to give off white light bouncing from it.

These flashes of colors are known as dispersion. The contrast of light and dark are is important to observe. If you do not know how a diamond is supposed to react to light and how other gems react to it, then you will have difficulty with this test.

Gems like cubic zirconia give off a rainbow-like color, which is very distinguishable from the white bright light color mentioned for diamonds. There is a big difference between the way a fake and a real diamond sparkle.

Top Ways to Find Out If Your Diamond Is Real or Fake

Bonus Tip!

This is a bonus tip for you since you have patiently read so far. Consider this as a bonus giveaway reward for knowledge. One of the best ways to spot a fake diamond is the Thermal test. (You will need a best and reliable tester for this)

The work of a diamond tester is to measure the level of thermal conductivity in a gem. This test only takes about 30 seconds, and make sure the gem is clean to prevent disruption.

This apparatus will show positive only for diamond and moissanite. You will have to acquire a diamond tester for this test. It can be found online for the amount of something around $15. Best if you could get one for yourself.

Final Thought

Many of the tests mentioned above will help you to confirm the genuineness of a gem. You will get to spot a fake diamond with most of these tests. It is the complexity of the imitations that makes it difficult for the tests to give 100 percent accuracy on the results.

Fake gems or synthetic gems are very hard to spot with just one or two tests. Some Replicas are very realistic that even they have their value in their own respective way, even if they were not presented as ‘fakes’.

It would be best that you visit a jeweler or a diamond expert to review your gem. They are highly trained when it concerns distinguishing between a fake and a real diamond.

Many diamonds that you purchase, comes with certified legitimacy from AGS, GIA, or IGI. You should carefully spectate on those certificates so that the diamond matches the numbers. While purchasing a diamond, you can ask for a grading report. They should be providing a grading report to you if ask for such assistance, so you can put your mind at ease and be free of worrying over its legitimacy.

Tests like fog tests and fire or shatter tests are very easy to perform. But do not get to a conclusion after only testing them out on few methods. Some tests are easy and have more accuracy than others, but that does not mean the final result would be always 100 percent accurate. The only way you can be 100% sure is if you to a jeweler or a gem lab.

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Welcome, everyone! Karl D. McGrath is an American Blogger and philanthropist based in the charming town of Thomasville, Georgia. As the founder of Ready For Ten, he is passionate about sharing his love for family, kids, home improvement, tools, outdoor activities, and kitchen gadgets with the world. With a natural talent for storytelling, Karl's writing style is warm, engaging, and down-to-earth. He has a gift for making even the most mundane topics come alive with his humor and wit, which has earned him a loyal following of readers who appreciate his honest and relatable voice. When he's not tapping away at his keyboard, Karl can be found spending time with his beloved wife, kids, and close friends. He is deeply committed to giving back to his community and works closely with several charities to make a positive impact on people's lives. Above all, Karl has a passion for making people laugh and feel good, whether it's through his writing, his charitable work, or simply sharing a joke over a cup of coffee. He is a true embodiment of the American spirit, and his dedication to family, community, and kindness is an inspiration to us all. If you would like to chat with him please feel free to reach out via facebook or twitter or email.

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