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Cultured freshwater pearls are pearls that are farmed and created using freshwater mussels. These pearls are produced in Japan and the United States on a limited scale, but are now almost exclusively produced in China. The U.S. Federal Trade Commission requires that farmed freshwater pearls be referred to as "freshwater cultured pearls" in ...
Pages in category "Pearls" The following 33 pages are in this category, out of 33 total. ... Cultured freshwater pearls; Cultured pearl; E. Ennerdale black pearl; F ...
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.
The freshwater pearl mussel (Margaritifera margaritifera) is an endangered species of freshwater mussel, an aquatic bivalve mollusc in the family Margaritiferidae.. Although the name "freshwater pearl mussel" is often used for this species, other freshwater mussel species (e.g. Margaritifera auricularia) can also create pearls and some can also be used as a source of mother of pearl.
Pearl farming in China is mainly concentrated in the southeastern part of the country, with the waterways of Zhejiang province serving as the source for China's freshwater pearls. [1] Production has greatly increased through the 1990s and 2000s, with China, according to Times Online , producing 90% of pearl necklaces globally. [ 1 ]
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.
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 ...
An annular cutter (also called a core drill, core cutter, broach cutter, trepanning drill, hole saw, or cup-type cutter) is a form of core drill used to create holes in metal. An annular cutter, named after the annulus shape , cuts only a groove at the periphery of the hole and leaves a solid core or slug at the center.