labgrown diamond Tempe

The 5 ways to tell if your diamond is real

Ok so it’s actually more than 5. When we started we had 5 in mind, but the more we wrote, the more things we came up with. You win!

Coveted for their rarity and beauty, diamonds are best known around the world for their sparkle, fire, and brilliance. Used for centuries in engagement rings, diamonds are iconic representations of love. But looks can be deceiving—there are many crystals out there that look very similar to diamonds but without the quality and durability of the real thing.

By just looking at a diamond or a crystal, it’s nearly impossible to tell if it is real or fake. Imitation diamonds, like cubic zirconia or zircon, oftentimes look nearly identical to actual diamonds—despite the fact that they are composed of totally different materials. But there are a few tips and tricks that will help you determine whether or not your stone is the real thing.

Learn more about how to tell if a diamond is real or fake, and test your own gemstones right at home.

1. In water, diamonds sink.

As the hardest gemstone known to man, diamonds are also extremely dense. This makes them durable and great for everyday wear but also makes them heavy. Because of their weight and density, diamonds sink when they’re dropped into a glass of water. Unlike diamonds, crystals are not nearly as dense. That means they tend to float just under the surface of the water or halfway in the glass.

To test your own stone, fill a glass of water. Drop the stone into the glass—if it sinks, you’ll know your diamond is real, but if it floats it means it’s an imitation. 

2. Diamonds don’t shatter when exposed to high heats.

Because it takes millions of years to form diamonds below the earth’s surface, they are exposed to massive amounts of heat and high pressure. As a result, diamonds are incredibly durable and aren’t susceptible to damage from high heat. Fake diamonds, on the other hand, cannot handle heat nearly as well because they are made of weaker materials.

To test the authenticity of your diamond, heat it with a flame—like a lighter—for 30 to 45 seconds. Be sure to hold the stone with tweezers or another tool to protect your hand. Once it’s heated, drop the stone into a glass of cool water. Real diamonds will simply fall to the bottom, while less durable, fake diamonds will shatter.

3. All diamonds have small, natural imperfections.

Because diamonds are naturally occurring, they all have some imperfections that were created as they formed in the earth. Alternately, man-made crystals are made to be perfectly smooth on both the inside and outside. That means they don’t have imperfections, known as inclusions, like real diamonds.

To tell the difference take a magnifying glass and inspect your gemstone. In good lighting, you should be able to see tiny imperfections throughout the stone if the diamond is real. If you don’t see any imperfections, it likely means that the diamond is not real.


4. Real diamonds turn blue under a black light.

If you have access to a black light, you can tell if a diamond is real very quickly. In a dark room, turn on the black light and hold up your stone. A large percentage of real diamonds turn a shade of blue under UV lighting because of the minerals inside the stone. Fake diamonds, on the other hand, will light a yellow, grey, or green shade. This drastic difference in fluorescence makes it easy to tell the difference between a real or fake stone.

5. Real diamonds don’t fog up as long.

If you take the stone and breath on it—whether it’s real or fake—it will fog up, just like a mirror. The difference, however, is in how long the fog lasts on the stone’s surface. With real diamonds, the fog will disappear quickly because diamonds conduct heat. This heat ensures that the moisture doesn’t stay on the surface long. Fake diamonds, however, can’t conduct heat so they will stay fogged up for several seconds. If you notice that the fog is long-lasting, it’s possible that the stone is fake.

6. What does it mean if a gem turns brown, then maybe green or yellow during the test?

When a gemstone undergoes a color change from brown to possibly green or yellow during the testing process, it typically indicates that the gem in question is a moissanite.

Diamond in the rough Phoenix

7. Which other gems have low or no heat sensitivity and may survive the test?

Several other gems have low or no heat sensitivity and may potentially survive the test. While the gem shattering indicates it is not a diamond, it could be cubic zirconia or glass. However, it’s important to note that this test alone cannot provide conclusive evidence that a surviving gem is a diamond. Gems such as moissanite, white sapphire, white topaz, white spinel, YAG (yttrium aluminum garnet), and GGG (gadolinium gallium garnet) are known to have low or no heat sensitivity and could potentially remain intact during this test.

8. What do the results of the scratch test indicate?

The scratch test is a method commonly used to determine how hard a material is. This test involves using a known gemstone or material with a known hardness to scratch the surface of the material being tested. The results, from this test can provide insights into the hardness of the tested material.

If the gemstone or material with a known hardness doesn’t leave any scratches on the tested material it suggests that the tested material is softer than the gemstone. For instance if we use quartz crystal for the test and it doesn’t leave any scratches it indicates that the tested material is probably not as hard as quartz. In cases there’s a possibility that it could be glass or another substance with a level of hardness.

On the hand if scratches are left on the tested material by the gemstone or material with a known hardness it suggests that its hardness is equal to or greater than that of the gemstone. This opens up possibilities, for identifying what kind of material it might be. While scratching quartz may indicate that it could be one of imitations scratching low grade corundum (sapphire) provides more specific information.
If a material is capable of scratching corundum it indicates that it could potentially be diamond, moissanite or white sapphire. All of which possess a level of hardness.

It’s worth noting that the scratch test is considered destructive meaning it has the potential to cause damage, to the gem or material being examined. If one wishes to maintain the appeal of the material it would be wise to refrain from conducting this test.

9. How does the newspaper/dot test work in determining if a diamond is real?

The newspaper or dot test is commonly employed to determine the authenticity of a diamond. This method takes advantage of the properties of diamonds particularly their ability to refract light. To conduct this test you will require a newspaper or a piece of paper, with a dot drawn on it. It’s important to note that this test is suitable for diamonds and not ones that are already set in jewelry.

To perform the test place the diamond face down on top of the newspaper text or on the paper, with the drawn dot. Take a moment to observe whether you can still perceive the shape of the letters or the dot through the diamond.

The results obtained from this test can provide insights into determining if your diamond is genuine. If you can still discern the shape of the letters even if they seem distorted or wavy it is highly likely that your diamond is not authentic. This happens because diamonds have an ability to refract light causing any text or dot viewed through them to become unrecognizable. In fact there’s a possibility that you won’t be able to see the dot all when conducting this particular test.

Hence if you can easily see the shape of the letters or the dot when placing the diamond facedown on a newspaper or paper it’s probable that the gem is not a diamond. This test relies on how diamonds interact with light allowing people to differentiate between diamonds and fakes.

10. How can I determine if a diamond is lab-made or mined?

The best way to accurately differentiate between a diamond created in a lab and one that is mined is, by having it evaluated at a laboratory. These specialized facilities have the expertise, tools and methods required to examine the diamond in question. By conducting tests and assessments that involve analyzing its chemical properties studying its growth patterns and evaluating any distinctive characteristics the gemological laboratory can provide an accurate determination of whether the diamond was grown in a lab or naturally formed through mining.

11. What do the results of these tests actually mean?

Each of the tests mentioned above provides insights, into the gemstone under examination helping determine whether it is a diamond or a counterfeit. Here’s a detailed explanation of what each tests results signify;

1. Thermal Test; This test measures the gemstone’s ability to conduct heat. A diamond tester will only show results for diamonds and moissanite. So if your gemstone passes this test there’s a probability that it’s indeed a genuine diamond.

2. Facet Doubling; Diamonds have singular properties while many imitations exhibit refraction characteristics. When examining the stone if you notice facets that appear doubled or blurry it could indicate that the gemstone is moissanite, white zircon, white topaz, quartz or white sapphire—indicating it is not a diamond.

3. UV Fluorescence; This test involves using a blacklight to observe how the gemstone reacts. If the stone emits a glow, under the blacklight it is more likely to be a diamond. However, if it glows in a color or shows no reaction all chances are it’s an imitation.

4. Newspaper/Dot Test;
To observe the bending properties of a gemstone try placing it face down on a newspaper or a paper, with a dot. Diamonds have refraction, which can distort and make the shape of letters or dot unrecognizable. If you can still see the shape of the letters or the dot it’s likely that the gemstone is not a diamond.

Another test you can do is the fog test. This involves checking how long it takes for fog to clear from a diamond or moissanite. Usually, they should only remain foggy for a few seconds before clearing up. If the gemstone remains fogged up for a period there’s a chance that it’s an imitation.

It’s important to remember that while these tests can provide insights they are not foolproof. For an assessment of authenticity, it’s recommended to have your diamond professionally tested by a jeweler or, at a gemological laboratory.

Teardrop Diamond

In the process of searching for the right diamond for your engagement in Scottsdale, Phoenix, Tempe, or Paradise Valley?

When purchasing a diamond, you should never even have to question whether the stone is real or fake. At Finer Custom Engagement Rings and Diamonds, our diamonds are only the finest GIA-certified stones.

With a wide array of caratscolor, cuts, and clarity, there is a diamond that is perfect for every ring and every proposal.

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