In most cases, the only reliable way to identify a real gem is to either have extensive training as a gemologist or a jeweler or to have access to intensive laboratory tests. These options aren’t always practical for the everyday shopper, but knowing a few tricks and tips can make your search for a legitimate stone much easier. One of the best places to start is to study the gemstone’s color spectrum and look at the arc of colors it produces in response to light. Real stones usually display a rainbow that will reflect on nearby walls and ceilings. Doing a bit of research on the characteristics of the specific stone you’re after will also help, and getting a professional opinion is almost always a good idea. It’s also really important to take your time, and not rush into a purchase decision based only on appearances.
Most real gemstones will produce a full spectrum of colors when exposed to light, sunlight in particular. In order to see what colors the gem you’re considering can produce, hold it up to any kind of light. By placing the stone close to your eye and tilting it, you should be able to see a variety of colors. A real gem will produce a rainbow of colors; stones that do not produce anything are frequently fake. This test isn’t definitive, though, and some stones, particularly those with very dense, deep coloring or those that haven’t been polished completely, may not respond. This doesn’t necessarily mean that they are illegitimate. If a stone does not create small bits of color, the best thing to do is to put it through another test, preferably one specific to the stone at issue.
Know Your Stone
There are many different gems, from diamonds and rubies to sapphires, emeralds, and more, and each has its own unique characteristics. Determining the real from the synthetic often takes a deep understanding of exactly what the genuine article should look like. It’s important to pay attention both to physical attributes and geographic or place indicators.
Take the time to find out about the qualities of the stone you’re seeking, everything from color to size to common weight. If your stone does not have the same specifications, you may not have the genuine article. Asking about origin can also be helpful. Certain stones only come from specific geographical locations, so something that seems to come from an unusual place may not be real.
Knowing something about how real gems are processed can also be helpful. You can usually get this information by asking a jeweler or gemologist whether or not any treatments have been done to the stone in question. Since many different treatments can turn a regular stone into a shiny gem impostor, purchasing a stone that has been treated with a laser or heat is not often a wise idea. Real gemstones are often cut and polished, but most have not gone through any other treatments.
Importance of Documentation
If you are shopping for an expensive gemstone, it’s often a good idea to ask a seller whether or not you can view the stone's certificate of authenticity. In most places, all gems “of worth” — which is to say, any gems that have significant value — are accompanied by a certificate of authenticity. If the stone you are considering purchasing does not have a certificate, find out if you can have the stone appraised prior to purchase. Any reputable jeweler should allow an independent appraisal without argument.
Take Your Time
It’s usually a good idea to take your time when shopping for gemstones. Look at a few stones before settling on one to get a feel for the market. Backing off can make counterfeit sellers nervous, and may also give you the chance to see if the price being asked is fair or normal in your region. Far too many people rush into purchasing a stone that has a good price and the guarantees of the seller without doing any investigating of their own. Real gems may be hard to spot, but with a bit of knowledge and preparation you should be able to distinguish the perfect stone from a synthetic rock.