Search results
Results from the WOW.Com Content Network
A pearl is a hard, glistening object produced within the soft tissue (specifically the mantle) of a living shelled mollusk or another animal, such as a conulariid.Just like the shell of a mollusk, a pearl is composed of calcium carbonate (mainly aragonite or a mixture of aragonite and calcite) [1] in minute crystalline form, which has been deposited in concentric layers.
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.
A black pearl and a shell of the black-lipped pearl oyster. The iridescent colors originate from nacre layers. All shelled mollusks can, by natural processes, produce some kind of "pearl" when an irritating microscopic object becomes trapped within its mantle folds, but the great majority of these "pearls" are not valued as gemstones.
Most molluscs with shells can produce pearls, but only the pearls of bivalves and some gastropods, whose shells are lined with nacre, are valuable. [ 18 ] : 300–343, 367–403 The best natural pearls are produced by marine pearl oysters , Pinctada margaritifera and Pinctada mertensi , which live in the tropical and subtropical waters of the ...
The mollusc (or mollusk [spelling 1]) shell is typically a calcareous exoskeleton which encloses, supports and protects the soft parts of an animal in the phylum Mollusca, which includes snails, clams, tusk shells, and several other classes. Not all shelled molluscs live in the sea; many live on the land and in freshwater.
The windowpane oyster (Placuna placenta) is a bivalve marine mollusk in the family of Placunidae. [1] It is edible, but valued more for its shell (and its rather small pearls). The oyster's shells have been used for thousands of years as a glass substitute because of their durability and translucence.
The western pearlshell (Margaritifera falcata) is a species of freshwater bivalve, a pearl mussel, a bivalve mollusk in the family Margaritiferidae. This species can be found only in the United States and Canada, where it occurs mostly west of the Rocky Mountains .
Pinctada margaritifera, commonly known as the black-lip pearl oyster, is a species of pearl oyster, a saltwater mollusk, a marine bivalve mollusk in the family Pteriidae. This species is common in the Indo-Pacific within tropical coral reefs. The ability of P. margaritifera to produce pearls means that