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 correct definition of a South Sea pearl – as described by CIBJO and GIA – is a pearl produced by the Pinctada maxima [21] pearl oyster. South Sea pearls are the color of their host Pinctada maxima oyster – and can be white, silver, pink, gold, cream, and any combination of these basic colors, including overtones of the various colors ...
This means that a Tahitian pearl can more easily grow to a larger-than-average size. [3] The cultured Tahitian pearl comes in various shapes, sizes, and colors; shapes include round, semi-round, button, circle, oval, teardrop, semi-baroque and baroque. [4] Because of their darker hues, Tahitian pearls are commonly known as "black pearls". [5]
Spanish emerald and gold pendant at Victoria and Albert Museum Enamelled gold, amethyst, and pearl pendant, about 1880, Pasquale Novissimo (1844–1914), V&A Museum number M.36-1928. Gemstones have no universally accepted grading system. Diamonds are graded using a system developed by the Gemological Institute of America (GIA) in the early ...
The Margarodidae (illegitimately as Margodidae) or ground pearls are a family of scale insects within the superfamily Coccoidea.Members of the family include the Polish cochineal and Armenian cochineal (genus Porphyrophora) and the original ground pearl genus, Margarodes.
Freshwater pearl harvests are typically bought while still in the shell. After harvest the pearls are delivered to a first-stage factory, which is responsible for cleaning and sorting the pearls by size and shape. After this process has been completed, the pearls are considered ready material for processing factories.
The original weight of this pear-shaped pearl was 223.8 grains, (55.95 carats, 11.2 g, almost .4 oz.). At the time of its discovery, it was the largest pearl ever found. In 1913 the pearl had to be drilled and cleaned to secure it firmly to its setting. After drilling and cleaning, the pearl's weight decreased to 203.84 grains.
Black-lipped pearl oyster Pinctada margaritifera: Pteriidae: Pearl oyster Y Pā [1]: 184 Pteria: Winged pearl oyster Pteria brunnea: Pteriidae: Pearl oyster Y Nahawele [1]: Isognomon: Black purse shell Isognocom californicum: Isognomonidae: Purse shell N Nahawele [1]: 186 Isognomon: Brown purse shell Isognocom perna: Isognomonidae: Purse shell N