pearl structure
Persian Gulf Pearl History Since the past, persian Gulf was one of the greatest source for fine and perfect pearls. Persian Gulf oysters (Pinctada margaritifera, Pinctada radiata) were collected for their mother-of-pearl, which was used as an inlay material in ancient Egypt as early as the sixth dynasty (c 3200 BC). The pearls of the Persian Gulf were natural created and collected by breath-hold divers. The secret to the special luster of Gulf pearls probably derived from the unique mixture of sweet and salt water around the island. Unfortunately, The natural pearl industry of the Persian Gulf ended abruptly in the early 1930 's with the discovery of large deposits of oil.
Figure1. Persian Gulf. Great source of wild-natural pearls
Pearl structure Most of the gemstone have a mineral and inorganic structure, but Since pearls structure comes from the organism, pearls originally have an organic structure. Inorganic gems are crystalline, while organic gems are non-crystalline so described as amorphous, or without the crystalline form. In the nature, pearls are found in black, white, pink and shades of other colors. Pearls have a distinctive concentric structure, and they have a specific gravity about 2.6-2.8. The main source of pearls are salt-water, such as persian Gulf, Japan, South Sea and Indian Ocean and fresh-water source and rivers including Mississippi and Amazon river. Pearls chemical composition are mainly calcium carbonate
(about 82%-86%), conchiolin and 2-4% of water (CaCO3 and H2O). Pearls are sensitive to heat and chemical materials. The bivalve of oysters are the best source for growing pearls. A good stimulus (usually a sand particle) is necessary for pearls production. The stimulus will place inside the oyster or mollusk, and oyster 's defense mechanism starts secreting a calcium carbonate coating material to coat the irritate.
Layer upon layer of this coating is deposited on the irritant until a lustrous pearl forms. It
Figure1. Persian Gulf. Great source of wild-natural pearls
Pearl structure Most of the gemstone have a mineral and inorganic structure, but Since pearls structure comes from the organism, pearls originally have an organic structure. Inorganic gems are crystalline, while organic gems are non-crystalline so described as amorphous, or without the crystalline form. In the nature, pearls are found in black, white, pink and shades of other colors. Pearls have a distinctive concentric structure, and they have a specific gravity about 2.6-2.8. The main source of pearls are salt-water, such as persian Gulf, Japan, South Sea and Indian Ocean and fresh-water source and rivers including Mississippi and Amazon river. Pearls chemical composition are mainly calcium carbonate
(about 82%-86%), conchiolin and 2-4% of water (CaCO3 and H2O). Pearls are sensitive to heat and chemical materials. The bivalve of oysters are the best source for growing pearls. A good stimulus (usually a sand particle) is necessary for pearls production. The stimulus will place inside the oyster or mollusk, and oyster 's defense mechanism starts secreting a calcium carbonate coating material to coat the irritate.
Layer upon layer of this coating is deposited on the irritant until a lustrous pearl forms. It
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