Cultured pearls are grown on pearl farms. These pearl farms generally have several thousand oysters. It can take as long as 2-5 years for a pearl to fully develop in the oyster. Pearl farming can be a risky business! The culturing of pearls requires a lot of skill and relies on some amount of luck. An entire bed of oysters can be completely devastated by such unpredictable and uncontrollable factors as water pollution, severe storms, excessive heat or cold, disease, and many other forces of both man and nature. Pearl farms control as many of these variables as possible.
In the early days of the cultured pearl farming industry, the oysters used by the Pearl farms to cultivate pearls were simply collected from the sea. Although some farmers continue using this method, the modern practice is to breed the oysters. The pearl farmer collects oyster sperm and eggs from high-quality oysters on the farm, and then uses the sperm to fertilize the eggs and create a new generation of oyster larvae. The larvae attach themselves to "collectors" which have been provided by the pearl farmers for this purpose. Over a period of a few months, the larvae develop into baby oysters. It takes perhaps 1-2 years, until they have grown sufficiently to be used.
The pearl farms nucleate an oyster by inserting a foreign object into the oyster. This object causes irritation, which the oyster counteracts by secreting nacre to surround the object, thereby producing a pearl.
Saltwater oysters are nucleated using a "bead" prepared from mother-of-pearl. The bead serves as a mold, so to speak, around which the pearl develops. The resulting pearl will contain the bead at its center and the pearl will tend to develop in the same shape as the original bead. Freshwater mollusks are nucleated using a piece of mantle tissue only. The pearl develops around the mantle tissue, which can over time deteriorate, leaving a pearl that is composed almost entirely of nacre.
The oysters are placed in cages or nets and moved into the oyster bed where they are allowed to develop. Depending on the type of oyster, this process can require anywhere from a few months to several more years. While the pearls are developing inside the oysters, the pearl farms pay close attention to water conditions, weather, and other factors which can influence both the health of the oyster and the development of the pearl. Water pollution is also a continuing concern, and pearl farms take numerous steps to insure the cleanliness of the water in which their oysters live.
After the pearls have been allowed to develop fully, they are extracted from the oysters, then washed, dried, and sorted into general categories. Sometimes the pearls are polished by tumbling them in salt and water. The pearls are then sold to jewelers, manufacturers, and pearl dealers.
