pearls

otheruses Pearl Island, Japan]]A pearl is a hard, rounded object produced by certain mollusks, primarily oysters. Pearl is valued as a gemstone and is cultivated or harvested for jewellery.Pearls are formed inside the shell of certain bivalve mollusks. As a response to an irritating object inside its shell, the mollusk will deposit layers of calcium carbonate !(CaCO₃)? in the form of the minerals aragonite or calcite (both crystalline forms of calcium carbonate) held together by an organic horn-like compound called conchiolin. This combination of calcium carbonate and conchiolin is called nacre, or as most know it, mother-of-pearl.The unique luster of pearls depends upon the reflection and refraction of light from the translucent layers and is finer in proportion as the layers become thinner and more numerous. The iridescence that some pearls display is caused by the overlapping of successive layers, which breaks up light falling on the surface. Pearls are usually white, sometimes with a creamy or pinkish tinge, but may be tinted with yellow, green, blue, brown, or black. Black pearls were highly valued because of their rarity; however, this does not apply nowadays as black pearl production has significanly increased.

History - Before the beginning of the 20th Century, pearl hunting was the most common way of harvesting pearls. Divers manually pulled oysters from ocean floors and river bottoms and checked them individually for pearls. Not all natural oysters produce pearls, however. In fact, in a haul of three tonnes, only three or four oysters will produce perfect pearls. Now, however, almost all pearls used for jewelry are cultured by planting a core or ''nucleus'' into pearl oysters. The pearls are usually harvested three years after the planting, but it can take up to as long as six years before a pearl is produced. This mariculture process was first developed by Kokichi Mikimoto in Japan, who was granted a patent for the process in 1896. The nucleus is generally a polished bead made from mussel shell. Along with a small scrap of mantle tissue from another oyster to serve as an irritant, it is surgically implanted near the oyster's genitals. Oysters which survive the subsequent surgery to remove the finished pearl are often implanted with a new, larger nucleus as part of the same procedure and then returned to the water for another three years of growth.The original Japanese cultured pearls, known as Akoya pearls, are produced by a species of small oysters no bigger than 6 to 7 cm in size, hence Japanese pearls larger than 10 mm in diameter are extremely rare and highly priced. In the past couple of decades, cultured pearls have been produced with larger oysters in the south Pacific OceanPacific and Indian Ocean. One of the largest pearl-bearing oysters is the Pinctada maxima, which is roughly the size of a dinner plate. South Sea pearls are characterized by their large size and silvery color. Sizes up to 14 mm in diameter are not uncommon. Australia is one of the most important sources of South Sea pearls. Tahitian pearls (also refered to as Titian pearls) are also another South Sea pearl.In the 1990s, Japanese pearl producers also invested in producing cultured pearls with musselfreshwater mussels in the region of Shanghai, ChinaShanghai, China, and in Fiji. Freshwater pearls are characterized by the reflection of rainbow colors in the luster. Cultured pearls are also produced using abalone.clear

Jewelry - The value of the pearls in jewelry is determined by a combination of the luster, color, size, lack of surface flaw and symmetry that are appropriate for the type of pearl under consideration. Among those attributes, luster is the most important differentiator of pearl quality according to jewelers. All factors being equal, however, the larger the pearl the more valuable it is. Large perfectly round pearls are rare and highly valued. Teardrop-shaped pearls are often used in pendants. Irregular shaped pearls are often used in necklaces.Pearls come in eight basic shapes, round, semi-round, button, drop, pear, oval, baroque, and ringed. Perfectly round pearls are the rarest and most expensive, and are generally used in necklaces, or strings of pearls. Semi-rounds are also used in necklaces or in pieces where the shape of the pearl can be disguised to look like it is a perfectly round pearl. Button pearls are like a slightly flattened round pearl and can also make a necklace, but are more often used in single pendants or earring where the back half of the pearl is covered, making it look like a larger, round pearl.Drop and pear shaped pearls are sometimes refered to as teardrop pearls and are most often seen in earrings, pendants, or as a center pearl in a necklace. Baroque pearls have a different appeal to them than more standard shapes because they are often highly irregular and make unique and interesting shapes. They are also commonly seen in necklaces. Ringed pearls are characterized by concentric ridges, or rings, around the body of the pearl.In general, cultivated pearls are less valuable than natural pearls, and imitation pearls are the least expensive. One way that jewellers can determine whether a pearl is cultivated or natural is by x-raying the pearl. If the grit in the centre of the pearl is a perfect sphere, then the jeweller knows it is cultivated. This is because when the cultivaters insert the grit, (usually a polished piece of mussel shell), it is always pefectly round, so as to produce a more expensive, perfectly round pearl. If the centre is not perfectly round, the jeweller recognises that it is genuine, and gives it a higher value. Imitation pearls are much easier to identify by jewellers. Some imitation pearls are simply made of mother-of-pearl, coral or conch, while others are made from glass and are coated with a solution containing fish scales called essence d'Orient. Although imitation pearls look the part, they do not have the same weight or smoothness as real pearls, and their luster will also dim greatly.There is also a unique way of naming pearl necklaces. While most other necklaces are simply refered to by their physical measurement, strings of pearls have their own set of names that characterize the pearls based on where they hang when worn around the neck. A ''collar'' will sit directly against the throat and not hang down the neck at all, they are often made up of multiple strands of pearls. ''Pearl chokers'' nestle just at the base of the neck. The size called a ''princess'' comes down to or just below the collarbone. A ''matinee of pearls'' falls just above the breasts. An ''opera'' will be long enough to reach the breastbone or sternum of the wearer, and longer still, a ''pearl rope'' is any length that falls down further than an opera.Necklaces can also be classified as uniform, where all the pearls are the same size, graduated, where the pearls are arranged in size from large in the centre to smaller at the ends, or tin cup, where pearls are generally the same size, but separated by lengths of chain.

See also -

Baroque pearl

NacreMother-of-pearl

Broome, Western AustraliaBroome

Ammolite - another organic gemstone formed primarily of fossil aragonite mollusk shells.

Oyster

External links -

!http://www.geo.utexas.edu/cour ses/347k/redesign/gem_notes/pe arl/pearl_main.htm

pearl-guide.com - Pearl Information Guide

paspaley.com.au - Paspaley - Leading supplier of Australian South Pearls

sspc.net - Southsea Pearl Consortium

robertwan.com - Robert Wan - Leading supplier of Tahiti Black !PearlsCategory:GemstonesCatego ry:Pearls!*bg:Перлаda:Perlede:Perle es:Perlafr:Perlehe:פנינהn l:Parelja:真珠ko:진주pl:Pe rłapt:Pérolaru:Жемчугs l:biserfi:Helmizh:珍珠 DEBUG REDIRECT (pearl)

Sara Nolte Designs
Handcrafted precious and semi precious gemstone jewelry & accessories. Our jewels & accessories are hand crafted one of kind item made with painstaking attention to detail. We create heirloom quality jewels just for you.
http://www.saranoltedesigns.com/

Gold Wolff Jewelers in Flagstaff, Arizona
Gold Wolff Jewelers specializes in custom made jewelry for those looking for that original and different piece. Don't settle for the same old thing that you could buy at any shop in your local mall. Have Gold Wolff make you exactly what you want. Our work is exquisite, unique, and reasonably priced. Why pay more for the same old thing, when you could have your own work of art.
http://www.goldwolff.com

Diva Pearls
Wholesale cultured pearl jewelry from pearl importer. Unique designs set in 14K, 18K, platinum. South Sea and Tahitian pearl strands, pendants, rings, earrings.
http://www.divapearls.com/

Beads and jewelry findings at Bluesage Beads
Shop for jewelry findings, glass beads and beading supplies at Bluesage Beads. Wholesale bead pricing with quantity purchases and free beading projects.
http://www.bluesagebeads.com/

Pure Pearls Jewelry
Find exquisite fine pearl jewelry, necklaces, earrings and sets of Akoya, Tahitian, Freshwater and South Sea pearls at up to 80% off retail prices from Pure Pearls. Free Shipping and GIA-certified appraisals included...
http://www.purepearls.com/

Pearl Guide
Information about the worlds oldest gem - the pearl. Discussion forum for consumers and professionals.
http://www.pearl-guide.com/

Belle Pour La Vie
A site totally dedicated to a beautiful you! Jewelry, flip flops,and body products are all combined on this site. Irrisitable prices and great designs. Come in and save.
http://www.bellepourlavie.com/

Essential Elegance, Inc.
Custom made Jewelry, One of a Kind pieces, Sterling Silver chains, 14KT Gold.
http://www.essential-elegance.com/

Pearls
Peals and fine pearl jewelry. The Pearl Outlet carries a wide selection of fine pearl jewelry at wholesale prices. Types of pearls include Akoya Saltwater pearls, freshwater pearls, Tahitian pearls, and South Sea pearls.
http://www.thepearloutlet.com/

American Museum of Natural History
Scientific research and education institution, with collections of more than 32 million specimens and artifacts.
http://www.amnh.org/

Comics.com
Features comic strips from United Feature Syndicate, Inc. - includes archives.
http://www.comics.com/

Pearls.com
Pearl pendants, earrings, necklaces and jewelry.
http://www.pearls.com/

London String of Pearls
The London String of Pearls Millennium Festival brings together the nations great institutions in a special programme of activities designed to open them up to the public, both physically and intellectually, and to explore and celebrate their role as building blocks of our society, today and in the future.
http://www.stringofpearls.org.uk/

The Pearls of Wisdom
Articles and guidance in some of lifes most basic foundations including attaining deeper levels of spiritual wisdom, achieving more fulfilling relationships, and finding meaning in life.
http://www.pearls.org/