Cultured pearls were initially developed for commercial purposes in Japan 100 years ago. Many oysters are now raised on farms for five or six years then removed from their beds. Skilled workers carefully open each oyster and insert a mother of pearl bead and a piece of mantle tissue into the shell. One oyster in three survives the procedure and produces a cultured pearl. These pearls are usually very large in size and precious and make beautiful pearl necklaces.

Nacre accumulates quite slowly in oysters and it takes about three years for a millimeters worth of nacre to accumulate and form a cultured pearl. Some pearl farms in the southern waters from Burma to Australia boast of a faster nacre buildup, in some cases up to three millimeters a year.

Because cultured pearls grow slowly, they are considered very rare and expensive. They make a lovely necklace and offer a more luxurious option for pearl jewelry lovers who do not like to sacrifice quality. Cultured pearls are generally larger in size than freshwater pearls.

The irritant is saltwater pearls is a shell bead nucleus, as well as a piece of mantle tissue. Saltwater oysters tend to die when the nucleus is inserted or when the pearl is harvested. Oysters only grow one pearl at a time. With one oyster in five providing a saleable pearl, price tags can be rather high. Japanese seawater pearls tend to be more expensive than Chinese seawater pearls mainly due to the higher labor costs and the higher quality produced. Japanese seawater pearl necklaces are generally more expensive and rare as compared to Chinese seawater pearl necklaces. Enhanced black cultured pearls are used to create fine royal necklaces. These pearls often come from China and Japan, and are actually white cultured pearls that are exposed to radiation or dyed to produce an even, strong color that lasts for years. Real cultured pearl necklaces need to be handled with care, as they are sensitive to heat and light.