It was the beginning of the 20th century when Japanese researchers discovered a way of purposely and consistently causing oysters to produce pearls. By artificially inserting a foreign substance into the oyster’s mantle, over a period of time a cultured pearl is created. In 1916, Kokichi Mikimoto perfected the process and patented his results. Today similar techniques are used to consistently produce a wide variety of cultured pearls in oysters and mussels. The size and shape of a pearl can also be pre-determined. This made cultured pearls viable for producing an abundance and wide variety of cost-effective and beautiful pearl jewelry.
Akoya Pearls are farmed primarily in China and Japan and cultured in the Akoya oyster. These oysters are the smallest of the group and generally produce pearl sizes in the range of 3mm to 11mm. Akoya Pearls are known for their high luster and slight pink or yellow hue.
Tahitian Pearls are farmed in the French Polynesian and around Tahiti by the “black-lipped” oyster. These oysters can grow in excess of one foot in length and tend to produce larger sized pearls up to 14mm in diameter. Tahitian Pearls are silver or charcoal in color usually with a slight green tint. Tahitian Pearls that are black are very rare and thus more expensive.
South Sea Pearls are cultured in two mollusk varieties: “silver-lipped” and “gold-lipped” oysters (Pinctada maxima). They are farmed in their natural water habitat around Australia, the Philippines, Indonesia, and surrounding areas. These large oysters produce pearls in the range of 9mm to 20mm and are among the largest pearls. Color varieties are typically white, silver, or golden with a satin luster.
Freshwater Pearls are cultured in mussels that live in non-saline water environments, such as lakes, rivers, and ponds. Most Freshwater pearls are farmed in China and it has been the country’s tradition since recorded over 4000 years ago. Freshwater Pearls are made of pure nacre thus tend to be more durable and less prone to chipping than their salt-water counterparts. These pearls usually range in size from 6mm to 12mm and come in a variety of colors and shapes and tend to have slightly less luster and usually less expensive than salt-water pearls.