More thorough methods of spotting a counterfeit gem

April 2, 2006 (Press Release) -- Dealers can also put a dab of paint on the bottom point of a dull gem to refract up through it intensifying the color. The light will go down through the gem and reflect off of the darker paint, the gem will appear a darker more valuable hue. A diamond that is too yellow can be painted on the bottom with a purple color thus counteracting the yellow and making the diamond appear clear. A crystal clear colorless diamond is worth more than a yellow one. The paint on the bottom of the gem will be hidden by the gold setting. Always make sure you can inspect the bottom of a gem in the ring’s setting. Do not buy an expensive ring with a closed back setting, the bottom of the gem may be painted.
A dealer can put a foil backing on an imitation glass stone to make the gem appear brilliant. Foil backing has been applied to gems for thousands of years; mostly before modern cutting techniques to add brilliant facets was invented. It is not a common practice today, but some antique stones can be found that have foil backings. The value of an antique stone with a foil backing will be valuable because it is an antique.
Sometimes gem manufacturers will glue together two stones to make a doublet, or three stones to make a triplet. These are called composite or assembled stones. When a seller discloses a doublet or a triplet this is not considered deceptive. But, sometimes the types of stones that are glued together are not equal in value. It is not uncommon for a synthetic stone to be glued to a natural or an imitation stone. When the buyer is not told it is considered a fraudulent practice.
Another misleading practice used by jewelers is re-naming gems to make buyers think they are getting a rarer more valuable one. A garnet could be called an American Ruby when all it is a garnet. Some other misnomers are: an oriental amethyst which is really a purple sapphire, a Brazilian diamond which is really a colorless topaz, an Indian emerald which is really a dyed crackled quartz, a Brazilian emerald which is really a green tourmaline, a Spanish emerald which is really green glass, a Ceylon opal which is really a moonstone, a water sapphire which is really iolite. This is just a few of them,
there are many more “manufactured” names dealers will give gems to make you believe you are getting more than you are. If a jeweler calls a gem by a double “special” name, ask them what it really means.
The above practices, when done with the intent to deceive, are fraud. If a jeweler or dealer is honest and discloses the information to the buyer then it is legitimate. As long as the buyer is aware of what they are purchasing then the sale is legitimate.

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