There are many options to consider if you want to know how to tell if diamonds are real.
Testing diamonds can be a tricky business. And there are many fake diamonds vs real diamonds out there.
These 10 tips will assist you in getting to the bottom of the age-old question…Is it a real sparkler or a piece of sparkly glass?
Jump To a Section Below
- How To Tell If A Diamond Is Real With Water
- How To Tell If A Diamond Is Real With A Flashlight
- Use Fog To Tell If A Diamond Is Fake
- The Diamond Setting And Mount
- Use A Magnifying Glass To Test For Real Diamonds
- Check If The Stone Shatters When Heated
- The Newspaper Test
- Use A Black Light
- Using a Loupe to Determine If A Diamond Is A Fake
- The Dot Test
How To Tell If A Diamond Is Real With Water
This test is incredibly basic but it will give quite a clear indication very quickly.
Fill a glass with water. This can be any water, even water straight out of the tap. Take the stone and drop it into the water. The test is quite simple – because of the density of a real diamond, if there is a possibility that it is real, the stone will sink to the bottom. If the stone floats to the top, or even rises just a small amount, this is a clear immediate answer that it is a fake diamond.
How To Tell If A Diamond Is Real With A Flashlight
Using a flashlight is a good way to start on how to tell if diamonds are real. Testing diamonds in this way will give a good indication of whether to proceed with further tests. Hold the diamond in the light from the flashlight, and observe how the light reacts with the stone.
What needs to be checked is whether the light being emitted is bright and sparkling. If this is the case, it has a good chance of being a real diamond. Fake diamonds will not reflect such bright shimmering and clear light.
Use Fog To Tell If A Diamond Is Fake
A quick test to perform is to hold the diamond up in front of your face and breathe onto it. Your warm breath should cover the stone in front of you. If the surface of the stones becomes easily fogged up and remains covered in this moisture for a few seconds, then the stone is probably a fake diamond.
If the stone does not fog up, it has a higher likelihood of being a real diamond. This is because water will not easily condense on the surface of a real diamond.
The Diamond Setting And Mount
How to tell if diamonds are real can also be done by checking the setting of the stone, if it is in fact set in a piece of jewelry. Because of the high value of diamonds, typically it will be set using a high-quality setting, and in much higher quality and higher value metal, such as white gold, yellow gold, or platinum. While this cannot be the only test, it is often a good starting point.
Use A Magnifying Glass To Test For Real Diamonds
Another way to test a stone for diamond authenticity is to use a magnifying glass. Hold the stone in question and look as carefully as you can inside the stone. What is interesting to note is that almost all diamonds are imperfect.
These imperfections are known as inclusions.
There are some diamonds that have no or virtually no inclusions – for the most part, these are made in laboratories, or otherwise, they are incredibly rare and as such, they are very expensive.
If you are wondering how are diamonds made, it is an interesting process. If there are no imperfections inside the stone, chances are that the stone is not a real diamond. If there are imperfections or inclusions, then there is a likelihood that it might be a real diamond.
Check If The Stone Shatters When Heated
Diamonds are incredibly high-quality stones, and because of this, they can withstand changes in temperature very well. If the stone is unable to withstand a temperature change, and fractures or splitters, it is not a real diamond.
Performing the test is quite simple. A pair of forceps will be needed, as the stone must be heated to quite a high temperature. Hold the stone in between a pair of forceps. Using a cigarette lighter, hold the flame under the stone for about 40 seconds. The stone will get really hot. At this stage, using the forceps, drop the stone into a glass of cold water. If it shatters, this is how to tell if diamonds are real.
The Newspaper Test
Place the stone on a sheet of newspaper. Look through the stone and attempt to read the writing on the page. If the writing is clear, or even if it is slightly blurry but still legible, then the stone is probably a fake diamond. Real diamonds refract light in all different directions, and so the writing will not be at all clear to read. This is a clear test for whether the diamond is fake or not.
Use A Black Light
In order to perform this test use a black light. Turn off all the lights in a room, and only shine the black light onto the stone. If the stone shows a light that has hints of yellow, green or even grey, the stone is likely not a diamond. If the stone gives off a blue or even a deep blue light, then the chances that the stone is a diamond increases. Importantly, this test is not conclusive. While this test will give a good indication, it should not be used conclusively.
Using a Loupe to Determine If A Diamond Is A Fake
Most people will not have a loupe. A loupe is used primarily by jewellers. It is basically a powerful magnifying glass that doesn’t have a handle. The method that can be used for testing diamonds is much the same as is done when using a magnifying glass. Look closely for inclusions. If no inclusions are evident, chances are that the question of fake diamonds vs real is that it will be a fake.
The Dot Test
The dot test is very similar to the newspaper test. Draw a small dot on a piece of white paper. Place the stone on top of this dot. Look through the stone and try to see the dot. If you can see the spot, even if it is blurry, or enlarged, then likely the stone is not a real diamond.
If the dot has disappeared, this means that the diamond reflects the light from the dot in different directions.
If this is the case, it may be a real diamond.
Next time you’re faced with what may be a flawless fake, try any of these tests to see whether or not the gem is the real McCoy.

Chermaine’s journey into the world of gemstones and crystals began as a child, collecting shimmering stones on family vacations. Today, she’s a certified gemologist and spiritual healer, intertwining the physical beauty of jewels with their metaphysical properties.
Chermaine has traveled to mines in Africa, marketplaces in India, and spiritual retreats in Bali, always seeking to deepen her understanding.