How To Tell If A Diamond Is Real

How to Tell If a Diamond Is Real

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Do you want to know how to tell if a diamond is real? Well, it can be tormenting to tell if a diamond is real or fake. Many people rely on professionals to find the answer. But, you can also check the authenticity of your diamond at home.

Buying a diamond is a major decision and it requires careful consideration. You need to be familiar with its features. Learning about a diamond’s structure and features can provide the answer to, “how to tell if a diamond is real.”

There can be numerous reasons to buy a diamond. Such as love, a tribute, or a gift. Whatever the reason is, you always need to know that the diamond you’re buying is real. Several fake counterparts can easily be mistaken for real diamonds.

In this article, we will explain 10 methods to spot a fake diamond at home. We will provide 6 professional diamond authenticity tests too. You will also get some tips to spot other stones that aren’t real diamonds.

Additionally, we will guide you about the expert tests you need to ask for before buying a diamond. And the things you need to do before buying a diamond. Keep reading this comprehensive guide for useful information.

10 Ways To Tell If A Diamond Is Real At Home

Want to check the authenticity of your diamond? With just a few simple tests, you can tell if a diamond is real at home. However, these tests must be done with extreme care for the diamond.

1. You Can Tell If a Diamond is Real Using Water

Spot Fake Diamond With Water

You can tell if a diamond is real using water. This water test is a straightforward and quick way to test the validity of a diamond. Here’s how you can do it:

  • Fill a regular glass to about three-quarters full with cold water.
  • Gently drop the diamond into it.
  • If the diamond sinks to the bottom, it’s real.
  • If it floats at the top or just underneath the surface, it’s possibly a fake.

Note: This has to do with a diamond’s high density.

Useful Tip: This method is suitable for a loose diamond. If it is set in a jewelry piece, the metal will cause it to sink. Thus, it won’t be an accurate assessment. 

2. You Can Check For Metal Markings To Test Diamond

Check For Metal Markings To Test Diamond

Can you tell if a diamond ring is real? Yes, of course! You might have a diamond already set in a ring. To tell if the diamond is real, check for metal markings. Look at the type of setting and mount. Inspect the metal for the markings and find out their meanings.

Due to a diamond’s hefty price tag, a real one is likely to be set in high-grade jewelry. For its protection and durability, a real diamond will not be set in low-quality metals. For instance, a real diamond is likely to be set in the following materials:

  • Yellow gold
  • White gold
  • Platinum
  • Pave or side-stone setting
  • Halo setting rings

To find the markings, check the inside of the ring. Here’s how you can find out their meanings:

MarkingsTheir Meanings
10K, 14K, and 18KIndicators of the type of gold used.
PT, Plat, or KaratRefer to platinum.
Numbers: 585, 770, 900, and 950Indicate platinum or gold.
C.Z. Engraving or StampThe gemstone is a Cubic Zirconia, not a real diamond.

3. Test The Diamond’s Authenticity Using Your Breath (The Fog Test)

The Fog Test

The fog test is very simple but effective. This one can be a effective solution when you’re finding answers of “How to tell if a diamond Is real”. Here’s how you perform this test:

  • Simply hold the diamond between two fingers.
  • Exhale on it with a puff of air to produce fog.
  • The heat and moisture from your breath will form a light fog on the diamond.
  • If the fog disperses instantly, your diamond is real.
  • If the fog takes more than a few seconds to disperse, the diamond isn’t real.

Note: Diamond conducts heat and as a result disperses heat instantly.

4. You Can Identify A Fake Diamond By Heating The Stone

Identify A Fake Diamond By Heating The Stone

Here’s another diamond authenticity test. Follow the following steps to perform this test:

  • Fill a glass with cold water.
  • Use a set of pliers to hold the diamond. You can also use fireproof gloves.
  • Heat the diamond with a lighter for 40 to 60 seconds.
  • Then drop it directly into the cold water.
  • If the stone shatters, it’s fake. With the shock of an abrupt temperature change, fake diamonds will shatter or crack.
  • Diamond is made of extremely strong material. A true diamond shows no reaction to heat.

This test checks the quality of the stone by testing its strength. Weak materials will crack and shatter due to the quick expansion and contraction of heat. Such as glass or cubic zirconia.

Diamonds are strong enough to be resistant to such heat tests. The temperature change will not affect the diamond. Also, the heat will go away quickly.

Note: This test can be problematic to do at home. It is only suggested if you have access to safe laboratory equipment. Like a beaker, safety glasses, and a Bunsen burner. You need to ensure the safety provisions to avoid possible injury.

Pro Tip: Even if you have a fake diamond, still it might have some sentimental value. Heat can destroy a fake stone. If you don’t want the stone to be destroyed, don’t perform this test.

5. Check Diamond Authenticity With Scratch Test

Check Diamond Authenticity With Scratch Test

How to spot a fake diamond with the scratch test? The scratch test was widely used to determine the hardness of a gemstone. It is a quick way to check if your diamond is real or fake. Here’s how you can perform this diamond authenticity test:

  • Slide the diamond smoothly along the mirror’s reflective surface.
  • If the mirror gets damaged, it’s likely to be a real diamond.
  • If the stone gets damaged, it’s obviously a fake.

Note: You need to have a loose stone to perform this test.

Limitation Of Scratch Test

This test might not work on some synthetic materials, like moissanite or cubic zirconia. These synthetic materials are scratch-resistant and quite durable. Moreover, your mirror can also get damaged.

So, that’s why the scratch test is not recommended. You should choose some other test in this situation. Like a thermal conductivity test. But, we recommend you have your stone inspected professionally.

6. Test A Diamond Using UV Or Black Light

Test A Diamond Using UV Or Black Light

One of the diamond authenticity tests is using UV light or black light. You can use a black light to differentiate a fake diamond from a real one. Not all of us have a black light at home. But if you have a black light at home, this is the simplest test to perform at home.

Here’s how you can do it:

  • Place your stone under the black light. Watch the reaction.
  • Most diamonds will shine blue under a black light.
  • Fake stones may glow in yellow, green, white, or gray color.

Useful Tip: The only light source should be the UV or black light. It’s a good idea to perform this test when it’s dark outside.

Limitation Of Black Light Test

The one limitation of this test is that not all diamonds will emit a blue-colored glow under black light. This should not be your only way to test your diamond’s authenticity.

Note: If your diamond shines blue under black light, you can feel pretty assured that it is a real diamond. But, if your diamond doesn’t, it doesn’t necessarily mean that it’s fake. You should still get it analyzed professionally.

7. You Can Spot Fake Diamonds Using A Magnifying Glass

Spot Fake Diamonds Using A Magnifying Glass

Can you use a magnifying glass to spot a fake diamond? Well, you need to have some experience in gemology. For amateurs, this test can be a difficult test to perform at home.

  • Inspect your diamond under a magnifying glass.
  • Look for imperfections.
  • If you find minor imperfections within the stone, it’s likely to be a real diamond.
  • If you can’t spot even a slight imperfection, the diamond isn’t real.

Flawless diamonds are very rare and extremely expensive. If your diamond is perfect, it’s most likely to be a synthetic stimulant. Not a real one. 

How To Tell If A Diamond Is Real At Home Using Refractivity

By looking closely at the diamond’s refractivity, you can distinguish a fake diamond from a real one. Diamonds refract the light passing through them. This results in their blindingly vivid appearance. Other stones like quartz and glass have a lower refractive index. That’s why they sparkle less. Here are two ways to test a diamond using refractivity:

8. Test Diamond With The Newspaper Method

Test Diamond With The Newspaper Method

This is a quite straightforward diamond authenticity test. Here’s how you can perform this test:

  • Turn your diamond upside down.
  • Place the flat side of it on a piece of newspaper.
  • If you can read the newspaper through the stone, the diamond is fake.
  • If the letters are a bit blurry or you see partial black smears, still it’s a fake.
  • If it’s a real diamond, you won’t be able to read the newspaper through it.

The facets of a real diamond don’t refract the light in a straight line. They rather bend the light sharply in different directions.

Limitations of newspaper test

  • The cuts of a real diamond might be disproportionate. In this case, you can read the newspaper through a real diamond.
  • Also, this test is only suitable for loose diamonds. If it is already set in something, you can’t perform this test. In this case, perform the fog test or have it examined by an expert.

Useful Tip: Make sure the lighting is bright. Also, there should be no shadow on the diamond.

9. Test Diamond With The Dot Test

Test Diamond With The Dot Test

When diamonds bend and refract light, they sparkle. When light hits the angled surfaces on the lower part of a diamond, it is refracted back through the diamond’s flat surface. This results in a radiant sparkle. And this sparkle is known as the brilliance of a diamond. Counterfeit diamonds don’t have this brilliance. Here’s how you can perform the dot test:

  • Place a piece of white paper on a straight table.
  • Draw a small dot with a pen on it.
  • Place the diamond on the dot with the flat surface facing down.
  • Look directly down through the pointed end.
  • Observe if you can see the dot or a reflection of it.
  • If it’s not a real diamond, you will notice a circular reflection of the dot.
  • If it’s a real diamond, you won’t be able to see the dot at all.

The light will be refracted in many directions in a real diamond. That’s why you can’t see the dot through a true diamond.

How To Spot A Fake Diamond Using Reflectivity

Besides refractivity, you can also test a diamond based on its reflectivity. Refractivity relates to the directions the light bounces. Reflectivity is the amount and quality of the light that is reflected off of the diamond. This includes both the brilliance and fire that shines off of a diamond’s flat surface.

10. Do Sparkle Test Using Reflectivity

Do Sparkle Test Using Reflectivity

You don’t need any equipment to check reflectivity except for your eyes. You can tell whether or not a diamond is real just by holding it under a light source. Here’s how you test your diamond using reflectivity:

  • Hold the diamond under a regular lamp.
  • Observe how light reflects off of the diamond.

Observing The Reflections Is The Tricky Part

Look straight down through the diamond’s table (the top surface of the diamond).

  • If you notice rainbow reflections, your stone is probably a low-quality diamond or a counterfeit.
  • If you notice different shades of gray, the stone is likely to be a real diamond.

A real diamond shows exceptional brilliance. But fake diamonds show relatively dull reflectivity. Such as Cubic Zirconia.

Pro Tip: Check for sparkles instead of reflections. A real diamond sparkles considerably more than a fake one of equal size. You should use a piece of quartz or glass as a reference.

Don’t Confuse Sparkle With Reflection

Sparkle refers to the intensity of the light that’s refracted by the cut of a diamond. But, reflection refers to the color of the light that’s refracted. So you should look for intense light, not colored light.


A moissanite is even more lustrous than a real diamond. Even some jewelers can’t tell the difference between a moissanite and a real diamond. However, you can spot a mossanite without using professional equipment. Here’s how:

  • Just hold it close to your eye.
  • Shine a flashlight through it.
  • If you notice rainbow colors, it’s a mossanite.

Rainbow colors are a sign of double refraction. And this is a feature of moissanite, not of diamond.

Can you tell if a diamond ring is real using a flashlight?

You can use a flashlight or regular lamp for the sparkle test. However, it’s best to use white light rather than yellow.

Additionally, don’t base your decision on this test alone. Perform other at-home tests too.

How Do The Experts Check If a Diamond is Real or Fake

How Do The Experts Check If a Diamond is Real or Fake

How do the experts check if a diamond is real? Jewelers and gemologists have different tools and techniques to get the job done. You can also learn to perform these expert tests at home. Here are 6 professional methods to spot a fake diamond:

1. Using The Loupe

A loupe is a small magnifying glass. It can be held close to the eye. A loupe can help you see tricky details clearly. It works better than a regular magnifying glass.

An expert will use a loupe to see whether the diamond has blemishes and imperfections. A real diamond is not flawless. There must be some imperfections if a diamond is real. These tiny imperfections are known as inclusions.

Diamonds certified by GIA usually have a micro-laser impression of the GIA report number. This number can be found on the edge of the diamond. It is very small and can only be seen by a skilled eye. Moreover, it requires at least 10x+ magnification to be seen.

2. Using The Diamond Tester

Another way used by professionals to spot a fake diamond is a diamond tester. It is a small electronic device that produces light and sound. This is also known as a thermal conductivity probe or meter. Gemologists use this device to find out the thermal conductivity of a diamond. Diamonds are great heat conductors.

  • A true diamond will diffuse heat quickly after being heated.
  • If the heat is dispersed slowly, the diamond is likely to be fake.

This test is inconclusive with moissanites. These synthetic stones have similar heat disbursement as real diamonds. A lot of diamond testers are available for you to choose from.

3. Subjecting The Diamond To High Profile Weighing

Jewelers and Gemologists use high-sensitivity scales. These scales can spot even tiny differences in weight. Also, these are far more precise than the typical scale. High-profile scales are capable of measuring down to the carat or grain level.

Real diamonds weigh less than their counterfeit equivalents. Such as Cubic Zirconia weighs about 55% more than a real diamond of the same size and shape.

Pro Tip: Choose a fake diamond equal in shape and size. Use it as a reference for the diamond in question. To get accurate results, making this comparison is essential.

4. Spotting a Fake Diamond Using Electricity Conductivity

A fake diamond can also be detected through an electricity conductivity test. This is one of the best diamond authenticity tests performed by the Jewelers or gemologists.

Diamonds are also incredible conductors of electricity. This test can tell you whether or not the stone is real or created by a lab. A real diamond will show electricity conductivity. However, other counterparts like cubic zirconia and moissanite will not show conductivity.

5. Performing A Microscopic Examination

Here’s how you can spot a fake diamond by a microscopic examination:

  • Place the diamond under a microscope with the flat surface facing down.
  • Take tweezers and shake the diamond gently back and forth with them.
  • If you notice a minor orange flash along the facets, the stone is actually Cubic Zirconia. It’s not a real diamond.
  • This may also show that Cubic Zirconia was used to fill inclusions within the real diamond.

Pro Tip: Use a 1200x power microscope to scrutinize the diamond in detail. You can easily see inclusions and minor differences in real diamonds compared to their counterparts.

6. Getting An X-ray Examination

Their X-ray test is performed to tell if the stone has a radiolucent molecular structure or a radiopaque molecular structure.

  • Diamonds have a radiolucent molecular structure. This means that they won’t appear in an X-ray.
  • Cubic Zirconia, Glass, and crystals have radiopaque features. They show up clearly on an x-ray.

You can submit your diamond to a professional diamond testing lab. Or you can get an X-ray examination at a local X-ray imaging center.

Expert Tests You Need To Ask For Before Buying A Diamond

Thinking about buying a diamond? You don’t want to be fooled by the diamond counterparts. Here are 5 expert tests that you must ask for before buying a diamond:

1. Ask For A Heat Probe Test

Heat probe tests are normally done free of charge. This test takes only about 30 seconds. Moreover, it doesn’t damage the stone the way some other methods of testing do.

2. Request Diamond And Moissanite Combined Testing

Many jewelers have expert devices that distinguish diamonds from moissanite quickly. These machines can also differentiate a real diamond from other stimulants.

3. Get A Microscopic Examination

Ask for a microscopic examination. A 1200x power microscope should be used to scrutinize the diamond in detail. You can easily see inclusions and minor differences in real diamonds compared to their counterparts.

4. Check The Diamond Under UV Light

A UV or black light test can help you distinguish a real diamond from other counterparts. However, don’t rely on this test as a definitive diamond authenticity test.

5. Get An X-ray Examination

Diamonds have a radiolucent molecular structure. This means that they won’t appear in an X-ray. You can ask for an X-ray examination from a professional diamond testing lab. 

How To Spot Other Stones That Aren’t Real Diamonds

How To Spot Other Stones That Aren’t Real Diamonds

Other stones that aren’t real diamonds are very popular these days. To the naked eye, these substitutes of diamonds will appear the same as real ones. It’s important to distinguish mined diamonds from these substitutions. Here’s how you can spot other stones that aren’t real diamonds: 

Recognizing Lab-Grown Diamonds / Synthetic Stimulants

How to tell the difference between lab-grown and natural diamonds?

  • The Main Difference: Lab-grown diamonds are real diamonds, but not natural.
  • Lab-grown diamonds can be around 30% less expensive than natural ones.
  • Compared to natural diamonds, lab-grown diamonds are more sustainable.
  • Lab-grown diamonds do not get the same resale value as mined diamonds.

Both natural and lab-grown diamonds have similar chemical and molecular properties. It’s nearly impossible for you to tell the difference. You will need the help of a diamond expert. A professional will run some expert diamond authenticity tests.

The everyday consumers will see no difference at all. They’ll still see that sparkle and fire they’d expect with a natural diamond. However, lab-grown diamonds aren’t valued as highly. We can mine a finite amount of diamonds from the Earth. There will be more lab-grown diamonds in the future. This will make natural diamonds even more valuable and rare.

Identifying Cubic Zirconia

A cubic zirconia is easy to spot through some diamond authenticity tests mentioned above. Here’s how you can get the job done:

  • The Sparkle Test: When light strikes the cubic zirconia, it exhibits a greater spectrum of color than real diamonds. A cubic zirconia reflects orange-tinted light.
  • High Profile Weighing: A cubic zirconia weighs more than a real diamond of the same size and shape.
  • Microscopic Examination: They lack the inclusions and blemishes, the imperfections of real diamonds.
  • The Scratch Test: Normally, the cubic zirconia becomes scratched itself in this test. However, some high-quality cubic zirconia can scratch the glass. So, this is not a conclusive way to spot a cubic zirconia.

Recognizing White Sapphire

Sapphires don’t only come in blue, but also in a variety of colors. A white sapphire looks clear to the naked eye.

White sapphires are often portrayed as real diamonds. However, they don’t exhibit the diamond’s sparkle and the sharp contrast of dark and light areas.

If your stone appears somewhat hazy or cloudy, it means its light and dark areas don’t contrast well. There’s a good chance that it is a white sapphire. The white sapphires are usually milky or more blurred in color. 

Spotting White Topaz

To the untrained eye, a white topaz may look like a real diamond. However, some characteristics separate it from a real diamond.

Diamond is the hardest material on Earth. It cannot be scratched by other minerals. But, the white topaz is softer than a real diamond and can be scratched easily.

If you notice any scratches on your stone, it is likely to be a white topaz. It can be some other soft substitute but not a real diamond. You can also examine your stone under a microscope to check for scratches.

However, a conclusive answer can be given by a trained diamond expert. 

Identifying Moissanite

Moissanites are the lab-grown versions of an extremely rare substance found in meteorite remains over 100 years ago. A moissanite is probably the best counterpart of a real diamond. Telling the difference between a moissanite and a real diamond is nearly impossible. It requires the expertise of a trained diamond expert.

  • A moissanite sparkles a little more than a diamond. It also yields a double refraction. Try shining a light through your stone. If it gives off a much more colorful and extra shine, it’s probably a moissanite.
  • Diamonds and moissanites have the same thermal conductivities. So, a thermal conductivity test is not the way to identify a moissanite.
  • Get a combined diamond and moissanite test to precisely identify moissanite.
  • An electricity conductivity test is the best way to distinguish a moissanite from a true diamond.  

Things You Need To Do Before Buying A Diamond

Here are 5 things that you must do before buying a diamond:

1. Find A Trustworthy Diamond Appraiser In Your Area

An appraiser can tell whether or not the diamond is fake. Diamond retailers employ gemologists and appraisers. However, you can also request an appraisal from an independent third-party appraiser.

Make sure that you get the stone appraised accurately by an expert and unbiased appraiser.

An appraisal is done in two steps:

  • Identifying and assessing the stone.
  • Assigning value to the stone.

How To Choose An Appraiser

It’s very simple:

  • An appraiser should have a Graduate Gemologist (GG) degree.
  • Make sure that the appraiser isn’t involved directly in the sale of diamonds.
  • An appraiser must be reliable.

Pro Tip: Never allow an appraiser to appraise your stone without your presence. Make sure that this is done in front of you.

2. Ask The Right Questions

A good appraiser can also answer various questions about the quality of your stone. Ask the right questions to make sure that you’re not getting scammed.

An expert appraiser should be able to tell you:

  • Whether or not the diamond is lab-grown or natural.
  • Whether or not the diamond has been color-transformed.
  • Whether the diamond has undergone a permanent or temporary treatment.
  • Whether a diamond is according to the documentation provided by a retailer.

3. Demand A Certificate Of Appraisal

The best and most trustworthy way to tell if a diamond is real is to check the paperwork. Consult a reliable gemologist or appraiser to understand the paperwork.

Certification guarantees you that your stone has been verified real by the experts.

Ask for a certificate as proof. Especially when you’re buying online.

How Are Diamonds Certified?

Diamonds are examined by experts and gemologists under laboratory conditions. Several reliable and professional bodies certify the real diamonds. Some are:

Gemological Institute of America (GIA)

The GIA is the most reliable and well-known diamond grading institute. They can provide the ultimate peace of mind while buying any diamond. You can either take your diamond to them or ship it to them.

American Gem Society (AGS)

The AGS grades diamonds from 0-10. 0 refers to the highest quality and 10 refers to the lowest.

International Gemological Institute (IGI)

The IGI is an international institute that certifies diamonds. They mainly focus on Asia and Europe. Some other grading authorities include LGP, PGGL, and AGSL.

4. Inspect Your Certificate Carefully

The certificates can also be fake. Make sure you inspect your certificate carefully. It must be from a grading authority as mentioned above. If it’s from an independent appraiser, make sure that the appraiser is associated with a professional institute. Like the American Society of Appraisers.

Certificates have information about your diamond, such as:

  • Carat weight
  • Measurements
  • Proportions
  • Clarity Grade
  • Color Grade
  • Cut Grade

Certificates from reputed institutes also have some extra information, such as:

  • Fluorescence: The ability of a diamond to give off a glow when placed under UV or black light.
  • Polish: The smoothness of a diamond’s surface.
  • Symmetry: The extent to which the opposite facets mirror each other impeccably.

5. Get Your Diamond Registered

After you know for sure that your diamond is real, take your diamond to a lab that can register your diamond.

Every diamond is unique, just like us humans. A fingerprint of your diamond will be taken by the registering lab. This will even ensure the safety of your stone.

Registration will cost you less than $100. Also, it can be good for insurance purposes. If a registered diamond appears on an international database, it will be spotted. You can retrieve your diamond by showing the registration documents. And prove that the stone belongs to you.

Final Thoughts

Well, that was everything on how to tell if a diamond is real. Diamonds are one of the most expensive and exclusive minerals. So, you need to be assured that you’re buying a real one. We have provided the diamond authenticity tests. You can either test your stone at home or get it tested professionally. Remember, the ultimate and conclusive way to test a diamond is to get it evaluated by an expert.

A lot of diamond-looking stones are available in the market. Make sure you know the difference. You must be aware of other stones that aren’t real diamonds. Stay vigilant and don’t fall for cunningly disguised replicas. Make sure you follow all the tips mentioned in this article. Always buy from a reliable and reputed source.

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