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How do you tell if diamonds are real?



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Here are several at-home exercises you can perform on a stone to determine whether or not it is a diamond.

NB: Your only infallible exercise is to take the diamond to a certified gemologist and pay for a document that confirms the diamond's cut, colour, clarity and carat weight.

At-home Exercises

The line or dot test

This simple visual test will tell you. Diamonds reflect light back out through the top surface (called the table) of the diamond. Cubic Zirconia, or CZ for short, is transparent and reflects the light differently.

  1. Draw a small dot or line on a clean piece of paper.
  2. Place the diamond / cubic zirconia in question face down on the dot.
  3. Look through the bottom.

If it is a real diamond you should not be able to see the dot or line; the image should be distorted. If your stone is a cubic zirconia (CZ) the dot will become a circle that is clearly visible.

The reason is that fake diamonds refract light differently than real diamonds. However some types of fake diamonds, such as those made with cubic zirconium oxide, synthetic rutile, fabulite and certain doublets can escape this detection method.

The Hardness Test - diamond is the hardest mineral known. Cut a piece of glass with it, like an old bottle or window. If it easily gouges the glass, it's either a diamond or a cubic zirconia. If it doesn't, it's glass.

Black Light Test- Diamonds have unique molecular properties. If you shine a black light (long-wave ultraviolet light ) on a stone and it will glow with different colors depending on what it is. A real diamond may gloe blue, cubic zirconia will glow mustard yellow, and glass will not glow at all.

Otherwise, take your jewelry to a qualified jeweler or gemologist and ask them to test your diamonds for absolute verification.

Only a jeweller can tell for sure if a diamond is fake or not, so do not throw out that stone, just because it seems to fail any of the three tests set out here.
bring them to a diamond cutter they have special tools to determine if its real