Water Test If you have a loose diamond to test, fill a regular glass about ¾ of the way full with water. Gently drop the diamond into the glass. If the diamond sinks to the bottom, it's real. If it floats at the surface or just underneath, it's likely a fake.
As straightforward as it sounds, fill a glass of water at home to roughly three-quarters full. Separate the stone so that it is loose, and drop it into the water. Diamonds are highly dense and a genuine gem will sink to the bottom – every time. If it hovers to the surface or only partially sinks, then it is a replica.
Two other quick and simple ways to spot a real diamond is by looking at how it sparkles in light and how much you can see through it. A real diamond appears gray and white inside (brilliance) when held to the light and can reflect rainbow colors (fire) onto other surfaces.
By holding a diamond close to a source of light, such as a flashlight, you can tell whether or not it's real. Watch closely for the shimmers of light that shine from the stone. A real diamond will reflect light easily, and provide you with a disco ball or rainbow-like display.
The free 4Cs app for Android is downloadable in English and Simplified Chinese. The GIA app is also available for iOS. A retailer version, designed for use at point of sale, is downloadable for free from GIA's retailer support site www.retailer.gia.edu.
If you have a loose diamond to test, fill a regular glass about ¾ of the way full with water. Gently drop the diamond into the glass. If the diamond sinks to the bottom, it's real. If it floats at the surface or just underneath, it's likely a fake.
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.
A sparkle test is quick and easy to do since all you need are your eyes. Simply hold your diamond under a normal lamp and observe the bright shimmers of light bouncing off the diamond. A real diamond provides an exceptional sparkle since it reflects white light extremely well.
Place the gemstones in a glass of water and watch. If it floats, then it is probably a fake stone. Real diamonds will sink to the bottom of the glass, while cubic zirconia will float to the surface.
An ideal cut diamond shows only a few intensely bright flashes in direct sunlight. A diamond that actually looks good in sunlight splits those few flashes up into ten or twenty smaller sparkles.
Diamonds are dense and will sink quickly, while certain imitations will sink more slowly. If your gem doesn't immediately sink to the bottom, it's likely a glass or quartz imitation.
A dirty stone doesn't sparkle because light simply can't enter the diamond and causes it to appear dull. So, if you notice your diamond jewelry getting cloudier overtime, it's likely due to a dirty surface and there's an easy fix to restore their luster.
Most synthetic diamonds look too good to be true all due to their extreme brilliance. Does your stone look really bright with lots of rainbow reflected colors? If so, it's most likely cubic zirconia. Yes, real diamonds are brilliant, but they are much more subtle than synthetics.
What is the stamp for diamonds on a ring? It depends on whether or not the diamond is natural or lab-created. If it's a real diamond, you can expect to see a stamp with carats and points. If it's made of synthetic gemstones like Cubic Zirconia, you may see a CZ mark.
Purchase a cheap piece of corundum or buy a mineral testing kit that includes corundum. Hold the corundum firmly against a table and scrape the suspected diamond against the corundum. If it creates a visible scratch, the crystal is a diamond. If it doesn't create a scratch, then it is a different mineral.
The most effective way to tell Moissanite apart from a diamond is to use a loupe to look through the top, or the crown, of the jewel at an angle. You will see two slightly blurred lines that indicates a double refraction, an inherent quality of Moissanite. Double refraction is easier to see in some shapes than others.
How Can You Tell the Difference Between Diamonds and Cubic Zirconia? The best way to tell a cubic zirconia from a diamond is to look at the stones under natural light: a diamond gives off more white light (brilliance) while a cubic zirconia gives off a noticeable rainbow of colored light (excessive light dispersion).
Does it Fog Up? The easiest at-home test is to breathe on your stone. If your stone fogs up quite a bit and takes time for the condensation to evaporate, then it is most likely fake. Real diamonds do fog up, but only a little and the condensation evaporates quickly.
The Mohs scale is a scientific measurement of mineral hardness. Glass is rated a 5.5, and diamonds, the hardest mineral, are a 10. So, genuine diamonds will scratch a mirror. On the other hand, so will quartz (7), moissanite (9.25), and cubic zirconia (8).
A diamond should have a clear, bright yellow or white color. A crystal will be off-white or cloudy looking. Yellow diamonds are becoming more and more popular, especially in the wedding ring market.
Fake diamonds do not reflect spectral rays from the beam of the flashlight. This is because a diamond's refractive index is high; it makes the white light entering the diamond split into multiple colors before it exits on the other side of the stone.
While it's true that diamonds are hard enough to cut glass, some synthetic gems can also scratch glass.