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Cultured Freshwater Pearls
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 commerce. Quality of cultured freshwater pearls is evaluated through a grading system of a series of A values, based on luster, shape, surface, colour and matching. Current and historic industry Pearls gathered in the wild from the Holarctic saltwater pearl mussel were important sources of pearls for modern jewelry, with Scotland a major source; this species is now endangered in most areas. Although the Japanese freshwater pearl industry has nearly ceased to exist, it has a normal historic place as the first country to cultivate whole freshwater pearls, which it did in Lake Biwa, using the Biwa pearly mussel (''Hyriopsis schlegeli''). The ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Necklace
The sea, connected as the world ocean or simply the ocean, is the body of water, body of saline water, salty water that covers approximately 71% of the Earth's surface. The word sea is also used to denote List of seas, second-order sections of the sea, such as the Mediterranean Sea, as well as certain large, entirely landlocked, saltwater lakes, such as the Caspian Sea. The sea moderates Earth's climate and has important roles in the water cycle, water, carbon cycle, carbon, and nitrogen cycle, nitrogen cycles. Humans harnessing and studying the sea have been recorded since ancient times, and evidenced well into prehistory, while its modern scientific study is called oceanography. The most abundant solid dissolved in seawater is sodium chloride. The water also contains salt (chemistry), salts of magnesium, calcium, potassium, and Mercury (element), mercury, amongst many other elements, some in minute concentrations. Salinity varies widely, being lower near the surface and the mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
