Some early stories say pearls grew from the tears of a goddess. Others tell of oysters swallowing raindrops or dewdrops that fell into the ocean. Round and lustrous, pearls symbolize the moon, and mortals have universally assigned feminine characteristics to them. Those who value gems for their powers wear pearls to attract love and good health.
Pearls are classified as organic gems because they are made by animals called mollusks. Mollusks have shells and most of them live underwater. They secrete a natural substance called nacre (rhymes with "acre").
Nacre consistes mainly of aragonite, a mineral crystal from the calcium carbonate family. The aragonite is combined with a natural "glue" called conchiolin and small amounts of water to form nacre. Nacre is also known as mother-of-pearl. The purpose of nacre is to make the inside of the shell smooth so that it doesn't irritate the soft body of the mollusk. A pearl is simply an abnormal growth of nacre.
Natural pearls are formed when something such as a grain of sand gets inside the shell and irritates the mollusk. To reduce the irritation, the animal covers it with thousands of smooth layers of nacre. The process is similar to what your body does when it forms a callus to protect irritated skin. It takes about three years to grow a small pearl.
Cultured pearls differ from natural pearls in that the irritant, usually a bead, is placed in the oyster by man. As cultured and natural pearls look alike, only an expert with special X-ray equipment can distinguish between them. Cultured pearls may not be sold as natural; however, they are regarded as "real" pearls and not fakes. Nearly all pearls on the market today are cultured, with most of them coming from Japan.
Pearls grow in many shapes, with round being the most highly prized. Some other symmetrical (even) shapes are pear, bell, and drop. A baroque pearl is one that is irregular in shape. Skilled jewelers often take advantage of the odd shapes of baroque pearls to make unique jewelry. Most popular are those shaped like animals or humans. If a pearl is rounded on one
