According to the contributing factor, pearls can be divided into two types: Natural Pearls and Cultured Pearls.
Both natural and cultured pearls are grown by oysters and are therefore considered valued jewelry gifts of nature. 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.
According to their living area, pearls can be divided into Freshwater Pearls, Seawater Pearls and South Sea Pearls.
The Variety of Cultured Pearls:
- Akoya Pearls (Grown in Japan and China)
Akoya pearls are the classic cultured pearls of Japan. They are the most lustrous of all pearls found anywhere in the world. In recent years, China has been successful in producing Akoya pearls within their own waters. However, at this time they are unable to produce as brilliant a lustre as high quality Japanese Akoya cultured pearls.
- Freshwater Pearls (Grown in Japan, China, and The United States)
Freshwater cultured pearls come from freshwater mussels and are produced by Japan, China, and The United States. Freshwater pearls come in various pastel shades of white, black, pink, peach, lavender, plum, purple, and tangerine, depending on the type of mussel. A single mussel can produce 10 or more pearls
Freshwater pearls are usually 100% of nacre, compared to saltwater pearls which are beaded.
The main production areas of freshwater pearls are in China, Japan and the USA. Typically, the US produces for its domestic market, whereas a good deal of the freshwater pearls from China find their way all over the world. Due to the transfer of technology from Japan, China is now able to produce high quality round pearls, whereas 10 years ago you would be hard pushed to find a near round Chinese freshwater pearl. Japan actually buys a lot of ‘raw’ pearls from China which it finishes and sells overseas as Japanese pearls.
- South Sea Pearls (Grown in Australia, Myanmar, Indonesia and the Phillipines)
South Sea pearls are saltwater pearls cultivated from the oyster, found in the South Seas centering on Northern Australia and South-East Asia including Myanmar and Indonesia. They produce 10-20 mm pearls of silver or gold color. For centuries, pearl divers harvested these exotic shells for their valuable Mother of Pearl shell to make buttons. Occasionally pearls were found inside, and these pearls were regarded as a rare and valuable bonus. They are larger in size than Akoya pearls and are used in the creation of fine pearl strands and ropes.
- Tahitian Pearls (Grown in French Polynesia)
Tahitian cultured pearls are grown in a variety of large pearl oysters found primarily in French Polynesia. Their beautiful, unique colors (which can range from light grey to black, and green to purple) and large size can command very high prices.
