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PEARLS- NGỌC TRAI

   

   PEARLS- NGỌC TRAI

·       Pearls are produced by oysters as everyone knows. They are composed of 90 percent argonite calcium carbonate, a substance applied to a nucleus of pearl by the same organ (the mantle) of the oyster that creates the shell, and 10 percent conchiolin, a gluelike protein that binds together the calcium carbonate crystals. Fossil pearls are abundant in 60 million-year-old rocks. [Source: Fred Ward, National Geographic, August 1985 ┦; David Doubilet, National Geographic, December 1991; Nigel Sitwell, Smithsonian]

·         Calcium carbonate is the material from which cement and limestone are made and argon is an inert gas like neon. This nacre is applied in layers about a thousandth of an inch thick. The growth pattern makes cultured and natural pearls feel rough when rubbed on the teeth. One advantage pearls have over gem stones and gold is that didn't require any cutting or smelting. They came straight from the shell ready to go. This was especially important to ancient people didn't the have the technology we have today to cut stone and produce metal.

·         Pearls come in a wide variety of colors and shades---silver, cream, old, green, blue and black---and seem to glow from within because light penetrates the surface and reflects off the inner layers. They respond differently to different kinds of light and enhance the color of a woman's skin Many people prefer pearls to diamonds because they believe they compliment a woman's beauty rather than upstage it. One gem buyer with Van Cleef & Areples told Smithsonian, "In the jewelry business, pearls are considered the most feminine of gems. I don't know a woman who doesn't lie pearls."

·         Early History of Pearls

·         Pearls were among the first precious stones to be worn by mankind. In ancient times pearls were featured in religious ornament and used for medicinal purposes and seen as symbols of purity, chastity and feminine charms.

·         Pearls were described in a 5,000-year-old Hindu legend about Krishna and a 4,300-year-old Chinese story of daughter the of a king. They are mentioned as symbols of wealth in the Talmud and the Bible and were found at 5500-year-old archeological sights in America and Europe. The ancient Greeks though that pearls were created by lightning struck by the sea. Other ancient peoples believed they were raindrops or dewdrops captured by clams.

·         The oldest surviving pearl necklace, dated to around 350 B.C., was found at Susa in western Iran, the home of a winter palace of a Persian king. Pearls were also unearthed in 2,500-year-old sites at Mount Albán Mexico as well as in ancient Peru.

·         Roman women adorned furniture and gowns with pearls and liked to sleep with pearls so "their dreams would be filled with lustrous gems." Caligula wore slippers covered with pearls and draped a pearl necklace around the neck of his favorite horse Incitatus; Nero decorated his scepter and Constantine his helmet with pearls; and one of reasons why Julius Caesar invaded Britain in 55 B.C. was to get his hand on freshwater pearls from Scotland. The Roman general Vitellus paid for an entire military campaigns by selling one of his mothers pearls.

·         The Romans though they were tears of the gods frozen inside of oysters. Cleopatra once bet Marc Anthony she could give the world's most expensive dinner party. To win the bet she crushed one of her pearl earrings and drank it in a goblet of wine. That one earring was said to worth 100,000 pounds of silver.

·         Pearls in the Persian Gulf

·         Pearl diving is believed to have been practiced in Bahrain for 4,000 years. The first reference to Bahrain pearling is a an Assyrian inscription from 200 B.C. that described "a parcel of fish eyes from Dilmun." In 100 A.D. the Roman chronicler Pliny described Tylos as being "famous for its vast numbers of pearls." Tylos and Dilmun were ancient names for Bahrain.

·         For centuries the Persian Gulf was the main gathering place of gem-quality pearls and Bombay was the home of one of the main pearl market. Arab sheiks in the 19th century amassed huge fortunes not from oil but from royalties on pearl gathering boats. In 1838, a British officer reported that Persian Gulf pearling industry was of comprised of 4,300 boats (3,500 of them in Bahrain) and 30,000 sailors, rope attendants and divers.

·         Around the turn of the century, there were about 900 Bahrain-based vessels engaged in the pearl fishing. In 1932, the ruler Rhaikh Hamad was appalled by the deplorable working conditions endured by pearl divers and he introduced financial reforms to give the industry sounder footing.

·         Until the early 1930s the pearl collecting trade was dealt two crippling blows: 1) the mass production of cultured pearls in Japan and 2) world-wide depression. Although the pearl trade is a shadow of its former self it counties to endure. Manama Bahrain was still the center of the natural pearl industry in the 1970s. Specialized pearl traders still work in the souks in Manama and Muharaq.

·         Pearl Collecting

·         Pearl diving is dangerous, seasonal work. The main pearl diving season is from June to October. The is also a "cold diving season" before and after the five-month diving season and their length varies according to the weather. During the pearling season, pearl divers live in seasonal pearling villages.

·         In the old days, great fanfare was made when the pearlers left their home villages for the seasonal pearling villages. Many worked from sambouqs and jalibuts, boats specially designed for pearl fishing and worked by 15 divers and 15 haulers who worked in teams. The ship has a single deck and the crew slept cramped together.

·         The Persian Gulf pearl industry relied on the labor of Indian and Arab divers, who worked under slavelike conditions and often had their lives cut short by their trade.

·         Pearl Divers

·         The pearling methods changed little over the centuries. The methods described by chronicler Abu Zayd Hassan in the 10th century were virtually identical to those used in early 20th century. Looped ropes with stone metal anchors wee tied to the boats. The diver used these ropes to descend quickly to the seabed. Their only equipment was a nose clip, finger-protecting-leather guards, a knife to cut open the shells and bag for the pearls.

·         The divers usually took two or three deep breath and leapt off the boat and descended to the oyster beds with a rope tied around a stone. Underwater they cut open as many shells as possible or placed as many oyster as they could in a basket and then tugged on a rope to be pulled up. When the divers needed air they tugged on the ropes and were pulled. After a few minutes rest they descended again.

·         One pearler told National Geographic in the 1960s, “When I was ready to dive I roped a heavy stone around one foot, slung a rope basket around my neck, and clipped shut my nostrils. I dived, and when felt my breath giving out, I tugged on th rope and my hauler pulled me up. I divided about 40 times a day. Some diver stayed down for four minutes and some only a minute and a half. An experienced diver would plunger 50 feet."

·         world's largest pearl On average each divers brought up between 200 and 400 oysters a day. The divers were often harassed by sharks (Marco Polo reported men who were paid to "charm the great fishes to prevent them from injuring the divers") and some reportedly kept diving even after limbs were bitten off.

·         Later Pearl History

·         The Koran describes paradise as being filled pearls and emeralds. Potions with ground pearls were consumed by Mogul emperors as an aphrodisiac and by Charles VI of France to treat his lunacy. Pearls were popular among royals because faceting technology for faceting gems was not invented until the mid 17th-century.

·         Queen Isabella and King Ferdinand told Columbus it was more important to bring back pearls than it was to return with gold, silver and spices. His discovery of large amounts of natural pearls in the "Pearl Coast" near the Orinico River off Venezuela triggered a rush to the area. So many pearling sites were discovered around the Caribbean after Columbus's voyage in 1492 that America was know in Spain for many years as the Land of Pearls.

·         Pearls were the most treasured gem until the 19th century when they were replaced by diamonds. Before cultured pearls dominated the market, most of the world's natural pearls came from the Persian Gulf. The island of Bahrain was the center of the pearl trade.

·         Famous Pearls

·         Vermeer's Girl with

·         the Pearl Earing According to the Guinness Book of Records, the largest pearl was the 14."pound Pearl of Lao-tze found in found in giant clam in May 1934; the largest cultured pearl was the 138.25-carat pearl raised near Samui Island in Thailand in January 1988; and the highest price paid for a pearl was $864,280 for a 302.68-grain La Régente pearl in May 1988. The pearl was originally part of the French Crown Jewels.

·         The world famous tear-drop-shape Le Peregrina pearl was discovered in the Gulf of Panama in the 16th century and was owned by several European royal families, In 1969, Richard Burton bought it for $37,000 at an auction as a Valentine's Day present for Elizabeth Taylor, who proceeded to lose it in the shag carpet of a suite at Caesar's Place in Las Vegas and found it slightly chewed up in her dog's mouth.

·         Famous pearls include a pair of pearl earrings given Napoleon to Josephine; a pearl-and-gem broach given by Prince Albert to Queen Victoria on their third wedding anniversary; a 10-gram, pear-shaped La Peregrina owned Liza Taylor; a pearl necklace given to Marilyn Monroe by Joe Dimaggio on their honeymoon in 1954. They were also favored by Jacqueline Kennedy and Grace Kelly.

·         Natural Pearls

·         Natural pearls have been described by Newsweek as the kidney stones of the mollusk world. They are formed when a parasite, piece of shell, or snail finds its way into a mollusk (rarely a piece of sand) and lodges between the shell and mantel (a soft tissue organ than lines the inside of the shell). Many kind of mollusks produce pearls but most of the time only oysters produce gem quality ones.

·         The mantel secretes nacre, or mother of pearl. Thousands of concentric spheres of nacre coats the foreign object and produce a pearl. Proteins from the mantel, trace elements for the water, can turn the pearls black, silver, blue, pink, cream or dove grey.

·         Oysters that produced natural saltwater pearls traditionally hailed from the Red Sea, the Persian Gulf, Sri Lanka, the islands of the South Pacific, the Gulf of Panama, the Gulf of California and other warm waters in the Americas. Mother of pearl comes from pearl oysters and abalone.

·         On average 1 in 40 or so oysters contains a pearl and most pearls found are misshapen. Only 1 in 2,000 are perfectly round. The largest known pearl is a 14-pound specimen that looks like a human brain.

·         Thousands of shells have to be collected to find a just a few pearls worth selling. An Australian pearl firm once bought up a hundred tons of shell without finding a single natural pearl worth over US$100. Today natural pearls are rare. Most pearls sold in jewelry stores are cultured pearls. Most of the buyers of natural pearls are rich Arabs.

·         Cultured Pearls

·         Cultured pearls are pearls cultivated from a spherical piece of shell, called a nucleus, placed into pearl oyster by a man. Layers of mother of pearl produced by the shell coat the nucleus and after six month to three years enough material has formed around the shell the pearl is ready for harvesting.

·         A perfectly round pea-size pearl sells for $75 to $100, compared to $4,000 for comparable natural pearl. It is difficult to tell a cultured pearl from a natural pearl by the naked eye. The primary difference is that a cultured pearl has a much more perfect shape. With a microscope you can see the surface texture of the two kinds of pearls is different.

·         The earliest forms of cultivated pearls were pearl Buddhas first produced in the 12th century by the Chinese. These tiny figurines were created by cementing a small Buddha carving of ivory, wood, stone or metal onto the shell of a freshwater mussel shell until they were coated with nacre. A similar technique is used today to create half pearls in freshwater oysters.

·         After hundred of years of trials and errors three Japanese working alone invented a technique for producing cultivated oysters at the beginning of the 20th century. One of the inventors was a teenage carpenter named Tatsuhei Mise and another was government marine biologist at Tokyo University named Tokichi Nishikawa. The other was Kokichi Mikimoto.

·         Kinds of Cultured Pearls

·         There are three main varieties of pearls: 1) white akoya pearls , mostly from Japan; 2) black, gold, white South Sea pearls, mostly from Tahiti, Australia and Indonesia; and 2) Chinese freshwater pearls.

·         Akoya pearls are 5 to 9 millimeters in diameter and

·         South Sea pearls have a diameter of 10 to 15 millimeters. Their thick nacre gives them their great size and a deep luster and makes them less likely to discolor of degenerate. . They are three to 20 times more expensive than Akoya pearls.

·         Kokichi Mikimoto and Cultured Pearls

·         Kokichi Mikimoto (1858-1954) was the man who created the cultured pearl business. The a son of noodle vendor from Mie prefecture in central Japan, he patented the world's first cultured round pearl and developed a method for producing "blister" (half pearls) and parlayed his patents into a massive fortune. At one time he owned 12 million oysters producing 75 percent of the world's pearls.

·         The first cultured pearl was taken from an oyster by Mikomoto's wife. It was semicircular. It took Mikimoto an other 12 years to coax the oysters to deliver perfectly round ones. When Mikimoto launched his cultured pearls in London in 1919 at prices considerably less than natural pearls he created a worldwide sensation. Producers of natural pearls claimed the cultured pearls were inferior but eventually they were driven from the market. The introduction of cultured pearls meant that pearls were no longer the domain of the rich. Flappers in the 1920s wore long strings of them.

·         Mikimoto was a master salesmen and promoter. He exhibited models of the Liberty Bell and Japanese pagodas made from cultured pearls at world exhibitions to get his product accepted as "real pearls." In the 1930s, Mikimoto famously set on fire 750,000 inferior pearls that threaten Japan's reputation as a producer of high-quality pearls. He also made news by addressing the Emperor and Empress with greetings below this normally used for royalty.

·         Mikimoto secured the patents for the tools and procedures to make cultured pearls. At first the oyster shells were harvested by the ama, the women divers, but later pearl farmers figured out how to grow baby oysters and have them ready to implant with nuclei in 60 days.

·         Making Cultured Pearls

·         Only a few species of oyster and freshwater mussels create quality pearls. On average, half of those seeded die or reject the bead. With luck 20 percent of the harvested pearls will be marketable and only 1 in 10 to one in 50 produce a round pearl of jewelry quality. The tools used for seeding and harvesting pearls resemble dental tools. A good technician can create different shaped pearls by the way he or she implants the bead.

·         Oysters relax and open when alone. Pearl seeders first place a wedge in the shell to keep it open and then make an incision with a surgical scalpel and insert a shell-bead nucleus (often a perfectly round pieces of mussel shell between .1 and .32 inches in diameter) into a tiny slit in the shell's fleshy mantle, which covers the interior of the shell.

·         Many of the nucleus are inserted in Japan by female technicians who can insert up to 1,000 nuclei a day (elsewhere in the world the work is done mainly be Japanese men). Perfectly placed nuclei result in perfectly round "eight-way-rollers." Misplaced ones result in misshapen pearls called "baroques." "Blister" pearls are cultured onto the shell rather than in the tissue.

·         Pearls can be raised in some species of freshwater oysters simply by cutting into the mantle. Most commercially raised oysters have been weakened by captivity and they are able to produce pearls only eight millimeters in diameter.

·         Pearl Products

·         Cultivated pearls are one of the world's cheapest gems. A US$1000 for a pearl necklace may seem like a lot of money. But consider that it is made up of 56 pearls which sell for $18.00 a piece. Necklaces selling for between $150 and $300 account for as much as 40 to 50 percent of the unit volume in trade.

·         The smallest pearls sold are about two millimeters in size. Eight millimeter pearl necklaces generally sell for two to three the price of a seven millimeter pearls. Today pearls are often bleached with hydrogen peroxide to remove blemishes and tinted with silver, cream, pink, yellow, green, blue and black dyes. No one is sure how pearls create their own natural colors. Five nuclei inserted into one oyster might produce five different colored pearls.

·         When buying pearls one dealer recommends that you purchase them from a trusted dealer, ask about nacre thickness, and stay away from ones obviously dyed. After purchasing them keep them clean and periodically restring necklaces. Pearls are also much softer than other precious stones. Body fluid, perfume and hair spray can eat away at the nacre and thinly coated pearls often have their nacre worn away after a couple of years.

·         Pearls too flawed to be sold as toothpaste are ground up in powder used in cosmetics and toothpaste as well as medicines to treat pregnancies, weak bodies, tooth cavities, stomach acid, and allergies.

·         Cultured Pearl Cultivation

·         Implanted oyster are returned to the sea, ideally for two to three years, in wire baskets suspended from wooden rafts or plastic buoys. After a few days in the water the inserted mantle tissue grows and wraps around the nucleus. Nacre is secreted from a sac in the mantle at the rate of a couple of layers a day (finished pearls have 1,000 or more layers of nacre around the nucleus).

·         Pearl oysters need unpolluted sea water, a relatively strong current and an ample supple of plankton. Occasionally the oysters are destroyed by typhoons, "red tides," and other natural events.

·         Pearls are produced by stress, Cultivators torture the oysters by washing their shells, moving them to different harbors, raising and lowering their cages, changing the water temperatures, They have to be careful. Too much stress caused the oyster to die.

·         The nuclei for almost all cultivated oysters comes from fresh water muscles found in the United States, mostly in Tennessee. The Japanese claim the nuclei all come from the American pigtoe mussel but actually most of these mussels were killed by pesticides and now the nuclei come from ten different species in the Unionadae family. The advantage these shells have over other species is that the shells are thick enough to fashion into a sphere accepted by the oyster. A single shell may yield 20 quality nuclei.

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