Pearl
Pearl is a hard object of gemstone, which produced within the soft tissue within the mantle of a living shelled mollusk. Just like the shell of a mollusk, a pearl is made up of calcium carbonate in minute crystalline form, which has been deposited in concentric layers.
The ideal pearl is perfectly round and smooth, but many other shapes of pearls are occur, sometimes being called as baroque pearls. The finest quality natural pearls have been highly valued as gemstones and objects of beauty for many centuries, and because of this, the word pearl has become a metaphor for something very rare, fine, admirable, and valuable.
The color of pearls varies with the mollusk and its environment. It ranges from black to white, with the rose of Indian pearls esteemed most. Other colors are cream, gray, blue, yellow, lavender, green, and mauve. All occur in delicate shades.
There are many types of pearls:
Natural pearls are pearl that made without human interference.
Cultured pearls are made when a foreign substance is intentionally inserted into a living oyster. This method was first used in 1893. Cultured pearls are being produced in virtually every color of the rainbow.
Baroque pearls are the pearls that have irregular shapes
Biwa pearls are irregular shaped pearl which forms in the freshwater of Lake Biwa, Japan
Blister pearls are pearls which grow attached to the inside of the shell
Black pearls are having the color of gray to black pearls
Freshwater pearls are pearls which form in fresh water mollusks and resemble puffed rice
Mabe pearls are cultivated blister pearls
Seed pearls are small, tiny pearls used in Victorian jewelry and sewn on clothing.
The finest Oriental pearls are found in the Persian Gulf. Other notable sources of fine-quality pearls include the Gulf of Mannar between India and Sri Lanka, the waters off Celebes, Indonesia, and the islands of the South Pacific. In the Americas, the Gulf of California, the Gulf of Mexico, and the waters of the Pacific coast of Mexico have yielded dark-hued pearls with a metallic sheen as well as white pearls of good quality.