Search results
Results From The WOW.Com Content Network
Cultured pearls have a similar color to natural pearls as the nacre is laid down by the mantle of the freshwater mussel, and thus the color of the pearl may be species specific. Exportation of freshwater mussels for the use in the Japanese cultured pearl industry has supported the North American freshwater mussel fisheries since the late 1950s.
This mussel produced a high volume of low-quality pearls that came to be known as "raisin pearls" in the 1970s and 1980s. More than a decade ago the freshwater pearl industry of China shifted production from the cockscomb pearl mussel to the triangle shell mussel ( Hyriopsis cumingii ).
The Pearl of Lao Tzu for a long time thought to be the largest pearl, but claims about its size and much of its history were found to be fabricated by a conman by the name of Victor Barbish. [2] Other pearls like the Centaur Pearl, most likely the largest gem pearl at 856.58 carats (171.316 g), have just recently emerged from private collections.
The cultured pearls on the market today can be divided into two categories. The first category covers the beaded cultured pearls, including Akoya, South Sea, Tahiti, and the large, modern freshwater pearl, the Edison pearl. These pearls are gonad-grown, and usually one pearl is grown at a time. This limits the number of pearls at a harvest period.
Tahitian pearls, frequently referred to as black pearls, [19] are highly valued because of their rarity; the culturing process for them dictates a smaller volume output and they can never be mass-produced because, in common with most sea pearls, the oyster can only be nucleated with one pearl at a time, while freshwater mussels are capable of ...
Margaritiferidae is a family of medium-sized freshwater mussels, aquatic bivalve molluscs in the order Unionida. [1] [2] It is the most threatened of all unionid families.[3]The family is sometimes referred to as the freshwater pearl mussel family, [4] but "freshwater pearl mussel" more often applies to the species Margaritifera margaritifera.
Pearl importers in consumer countries, and the trade associations they constitute, have recommended limiting the use of the term keshi to ocean pearls, and banning its use for freshwater pearls. This is justified to some extent by the fact that ocean pearl keshi were known as a product for some years before their freshwater counterparts.
In contrast, one of the largest species of freshwater bivalves is the swan mussel from the family Unionidae; it can grow to a length of 20 cm (7.9 in), and usually lives in lakes or slow-flowing rivers. Freshwater pearl mussels are economically important as a source of pearls and mother of pearl. While some species are short-lived, others can ...