An external object, such as a sand grain or tiny parasite, comes into a mussel and cannot be excreted. To relieve irritation, the mollusk coats the gatecrasher with a secretion it uses for building it's shell, called nacre. In cultured freshwater pearl production, workers ease the mussel half shells apart and cut small slits into the mantle tissue inside both shells. Then they introduce minute pieces of live tissue from a different mussel into the slits. That is enough to start nacre production. The majority of cultured freshwater pearls are made entirely of nacre, just like their natural counterparts. Culture of fresh water pearls began in Japan. After their successes with culturing saltwater pearls, Japanese pearl farmers experimented with freshwater mussels in Lake Biwa. The early freshwater commercial crops came out in the 1930s. The all-nacre Biwa pearls featured colors never seen in saltwater pearls. Depth of luminescence and lustre matched naturals. In fact, until recently, all fresh water pearls were called "Biwas," no matter where they came from. Japan dominated the market.
Although you will still hear people talk about Biwa pearls, today's freshwater pearl production is mostly from China. Production has in Lake Biwa has ended due to pollution and excessive harvesting. In 1994 Japanese pearl farms were devastated by "red tide," a threatening influx of toxic micro-organisms that killed over 150 million pearl-producing oysters by 1996. Also in the Chinese pearl farmers favor is the many large lakes and rivers combined with an equally large cheap labor force. This change is a complete transformation in the previously stable pearl industry, and amounts to immense savings to you, the consumer.
The Black Pearl may have been a ship in a movie but the black pearls in a black pearl necklace come from the South pacific islands and are often called South Sea Pearls or Tahitian Pearls.
Are you interested in pearls? Epecialized in wholesale cultured pearls jewelry imported from all over the world. Once one understands the variety of wholesale pearl strands, cheap pearl necklace, freshwater pearl bracelet, pearl rings, pearl earrings, cheap pearl pendant, 925 sterling silver jewelry, cultured pearl beads … available (the different shapes, sizes, colors and qualities of pearl beads) then one can identify or compose the single strand necklace that is appropriate. You can check out a good website which I saw suddenly. You can check pearl necklace page for more information. This will explain about the quality of all the different types of pearls. Enjoy yourself.
Orignal From: An external object, such as a sand grain
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