The only difference between them is that natural pearls begin by accident while cultured pearls are initiated by man. A skilled jeweler can usually look down the drill hole of a pearl and determine the origin. However, the only sure way to tell the difference between a natural and cultured pearl is by using an X-ray machine. Imitation pearls, on the other hand, are man made by mechanical processes and have no real jewel value. Better imitation pearls are made from beads of glass, ceramic, shell, or plastic which are coated with a varnish generally made of lacquer and ground fish scales to simulate the iridescence and color of a pearl.
Imitation pearls go by many names.
Some, unfortunately, are used to mislead consumers. The words fashion, faux, simulated, organic, man-made, Mallorca , or simular regional names are all terms that are currently applied to manufactured, imitation pearls. Most pearl experts can readily tell the difference between imitation and real pearls by sight alone. However, due to sophisticated manufacturing and polishing techniques, it may be difficult for the average consumer to distinguish a natural or cultured pearl from a good imitation by sight. An easy way to tell the difference is the tooth test.