Buying diamond jewelry is a costly pleasure many of us can barely afford. And because it’s so expensive, customers should keep their eyes open, as many try to pass other stones as real diamonds. There are several ways to tell if a diamond is real or not, but none of them provide 100% accuracy. Nevertheless, you can get an idea if you’re being tricked or not from the very beginning.
Due to their chemical structure, diamonds disperse heat instantly and do not fog under any conditions. Zirconium stones do stay fogged from 2 to 4 seconds, but the accuracy of the test is not full proof. You will not get a very good idea if there’s oil or dust on the stone or if your piece of jewelry has a diamond on the top and zirconium at the bottom.
Checking the setting and mount is another way to tell if a diamond is real or not. Diamond rings and diamond pendants usually come with metal stamps. Since real diamond will not be set in a low-cost metal, look for stamps such as 10K, 14K, 18K, 585, 750, 900, 950, PT and Plat. Keep in mind that CZ stands for Cubic Zirconia, which is pretty much worthless.
Get a jeweler's loupe and inspect the gem. Look for small imperfections or inclusions, as they are called. Also look for slight color changes between facets. Cubic zirconia does not have those natural flaws, as it is synthesized artificially. Still, some diamonds can be flawless as well. Lab-made diamonds also lack imperfections.
The stone's refractivity is another factor to determine whether it is real or not. The light that passes through diamond is bent in a sharp way, creating the brilliant appearance. If you can see clearly through the stone and even read through it by placing it on a newspaper, then it isn’t a real diamond. Still, if the diamond was cut in a disproportionate way, the print might be readable through a real diamond as well.
Another way to test the refraction is by drawing a dot and placing the center of the stone on top of it. Of course, this applies to un-mounted diamonds. If you can see a round reflection, the stone is probably fake. A diamond reflects light in shades of gray. Only low quality diamonds or other stones create rainbow colored reflections.
Some stones such as moissanite, copy diamonds so well, they sparkle just as brightly. To tell them apart, look closely at the stone, while placing it against a penlight. If you see it shine in rainbow colors, then it’s not a diamond. Double refraction is a property of moissanite.
Heat the stone for a few seconds and immerse it immediately in cold water. If it is not diamond, it will shatter because of the shock produced by heat expansion and contraction. Also, diamonds conduct heat, so they will not heat up easily. Diamonds sink in water while other stones tend to float.
Many but not all diamonds will show a blue fluorescence when exposed to UV light. Green or yellow fluorescence is a sign that the stone is moissanite. It is advisable not to rely on this test solely, as some fake stones were created to exhibit the mentioned fluorescence.
Have it Tested by a Professional
Ask an expert to place the stone under a microscope with the top facet facing down. If the stone displays orange reflections when rocked, then it might be cubic zirconia. In some cases, cubic zirconia is used to fill the imperfections of diamonds, so don’t get nervous.
Weigh is another indicator whether a diamond is real or not. Regardless of their high density, diamonds are lighter that other stones of the same size and shape. For example, zirconia is about 55% heavier than a comparable diamond. It would be really useful to have a real similar diamond around to compare weights.
Diamonds don’t appear in x-ray images, as they have radio-transparent molecular structure. Glass, cubic zirconium and crystals do appear in x-ray images. To perform such a test, you need to seek the advice of an expert.
Diamonds conduct electricity. But so do moissanites. To tell them apart, an expert will run through the stone a small electric current and evaluate the intensity. Although both stones conduct electricity, they do it differently. And an expert will tell them apart.
Get a Grading Report
Look for gemologists in your area and request an appraisal report. A grading report will identify the stone and calculate its value. A good appraiser can also provide a few details about your precious stone.
You can find out if the stone is artificial, if the colors have been altered or if permanent or temporary treatment was applied to it. If the stone already has a grading certification, an expert can tell you if the information there is accurate.
Request a certificate of appraisal, especially if you’re purchasing online diamond rings or diamond pendants and check it carefully. The certificate should be issued by a renowned authority, and should contain lots of information such as carat weight, size, clarity grade, color grade and cut grade. Information about fluorescence, polish and symmetry can also be included.
Have it Registered
When you get the certification, have it registered and fingerprinted. That way you will make sure no one can switch your jewelry with fake ones later. Keep in mind that diamonds are unique, and fingerprinting contributes to that uniqueness. If your jewelry is stolen and is found in an international fingerprint database, you can get it back by showing necessary documentation to prove it’s yours.
Getting a certificate from a reputable grading authority is the only way to make sure the stone is real. Scratching your stone against other surfaces will not prove anything, but it will lead to the deterioration of the stone.