How to Identify a Real Diamond

How to Identify a Real Diamond

Those who enjoy shopping for vintage jewelry in unconventional places know that there are valuable treasures waiting to be discovered. Whether you're looking at antique shops,

, consignment shops or even yard sales, it's always good to have a few tricks up your sleeve to help you better determine if that flashy stone or meek, dirty gem is really a diamond.

Things You'll Need:



Diamond tester


Observe the mounting. Real diamonds will be set in precious metals, and most likely in an open setting. Though not a guarantee of a fake, if the setting has a closed back, then more than likely the gem is not a diamond.


Breathe on the stone. Diamonds are excellent conductors of heat, so you should not be able to observe any condensation on the stone if it is a real diamond.


Rub sandpaper across the surface. A diamond will not scratch or nick from this procedure, but a fake might. If you're buying directly from an individual and they refuse to let you do this, then you can be confident that it is probably not real.


Be skeptical of scratched glass. Though this is a popular technique, keep in mind that glass is only rated 5.5 on the Mohs hardness scale. While a diamond is rated a 10 on the Mohs scale, anything higher than a 5.5 will still scratch glass. Quartz rates at 7.5 and cubic zirconium rates in at 8.5, so this test won't work at all.


Place the diamond on a piece of newspaper over the text. If you can see the letter at all, whether clearly or as a hazy likeness, your gem is not a diamond. A diamond's brilliance, even a poor specimen, refracts light so dramatically that you won't be able to see anything through the stone.


Use a diamond tester. These handy gadgets will run about $100, but if you're regularly on the hunt for diamonds it may be a good investment.


Look for flaws. Diamonds are not perfect, and even the best specimens will have tiny flaws. If the stone is perfectly clear then be skeptical of it being a diamond.

Tips & Warnings

Some auction houses and antique dealers will offer free appraisals.

Nothing is a sure fire identification except an evaluation by a certified gemologist.

Though any jeweler will be able to identify a stone as a diamond, they may not be able to tell you the true value of a piece of jewelry beyond the materials used. If you have an antique piece, take it to an antique dealer to learn its true value.