Gem Treatments and Enhancements
A treatment, or enhancement, is a way of adding beauty to a stone.
Some treatments bring out the stone's inherent qualities. Emeralds, for example, are routinely oiled to bring out their color. Such treatments do not camouflage flaws or harm the stone in any way. The jewelry retailer need not specifically mention treatments that are regarded as the usual way of dealing with that kind of gem (as described in The Gemstone Enhancement Manual, the jewelry industry's standard reference for gem treatments).
Other treatments are done to stones of lower quality to make them appear more attractive. Although a trained gemologist can see, under a microscope, that the stone has been treated, the purchaser cannot. If the seller does not disclose such treatments, a customer would believe the gem to be of higher quality than it is and might be led to pay a higher price.
All treatments that are not accepted as part of the normal processing of a gem should always be specifically disclosed, both verbally and on the sales receipt.
Improved technology brings new enhancements
As the technology improves, the variety of enhancements proliferates. An official of the American Gem Trade Association declared recently that enhancements are prevalent today because "the consumer has developed these unreal expectations of what they want in a gemstone." Consumer expectations, however, have been fed by what the marketplace seems to offer: beautiful gems at lower and lower prices. Often low priced gems are really low quality stones that have been treated.