Throughout history, pearls have held a unique presence within the wealthy and powerful. For instance, the pearl was the favoured gem of the wealthy during the Roman Empire This gift from the sea had been brought back from the orient by the Rome conquests. Rome women wore pearls to bed so they could be reminded of their wealth immediately upon waking up. Before jewelers learned to cut gems, the pearl was of greater value than the diamond. In the Orient, pearls were ground into powders to cure anything from heart disease to epilepsy, with possible aphrodisiac uses as well. Pearls were once considered an exclusive privilege for royalty. A law in 1612 drawn up by the Duke of Saxony prohibited the wearing of pearls by nobility, professors, doctors or their wives in an effort to further distinguish royal appearance. American Indians also used freshwater pearls from the Mississippi River as decorations and jewelry.
There are essentially three types of pearls: natural, cultured and imitation. A natural pearl (often called an Oriental pearl) forms when an irritant, such as a piece of sand, works its way into a particular species of oyster，mussel, or clam. As a defense mechanism, the mollusk secretes a fluid to coat the irritant. Layer upon layer of this coating is deposited on the irritant until a lustrous pearl is formed.
A cultured pearl undergoes the same process”’ The only difference is that the irritant is a surgically implanted bead or piece of shell called Mother of Pearl. Often, these shells are ground oyster shells that are worth significant amounts of money in their own right as irritant-catalysts for quality pearls.The resulting core is, therefore, much larger than in a natural pearl. Yet, as long as there are enough layers of nacre (the secreted fluid covering the irritant) to result in a beautiful, gem-quality pearl, the size of the nucleus is of no consequence to beauty or durability.
Pearls can come from either salt or fresh water sources. Typically, saltwater pearls tend to be higher quality, although there are several types of freshwater pearls that are considered high in quality as well. Freshwater pearls tend to be very irregular in shape, with a puffed rice appearance the most prevalent. Nevertheless, it is each individual pearls merits that determines value more than the source of the pearl.
Regardless of the method used to acquire a pearl, the process usually takes several years Mussels must reach a mature age, which can take up to 3 years, and then be implanted or naturally receive an irritant. Once the irritant is in place, it can take up to another years for the pearl to reach its full size. Often, the irritant may be rejected, the pearl will be terrifically misshapen, or the oyster may simply die from disease or countless other complications. By the end of a 5 to 10 year cycle, only 50% of the oysters will have survived. And of the pearls produced, only approximately 5% are of substantial quality for top jewelry makers From the outset, a pearl farmer can figure on spending over $100 for every oyster that is farmed, of which many will produce nothing or die.
Imitation pearls are a different story altogether. In most cases, a glass bead is dipped into a solution made from fish scales This coating is thin and may eventually wear off. One can usually tell an imitation by biting on it. Fake pearls glide across your teeth, while the layers of nacre on real pearls feel gritty. The Island of Mallorca is known for its imitation pearl industry.
To an untrained eye, many pearls may look quite similar. There is，to the contrary, an intricate hierarchy to pearls and several factors exist that determine a pearl’s worth. Luster and size are generally considered the two main factors to look for. Luster for instance, depends on the fineness and evenness of the layers. The deeper the glow, the more perfect the shape and surface, the more valuable they are. Moreover, if you can see a reflection of your face clearly by gazing into the pearl, that is a high quality luster. The foggier the reflection, the less valuable the pearl Size on the other hand, has to do with the age of the oyster that created the pearl (the more mature oysters produce larger pearls) and the location in which the pearl was cultured. The South Sea waters of Australia tend to produce the larger pearls; probably because the water along the coast line is supplied with rich nutrients from the ocean floor. Also, the type of mussel common to the area seems to possess a predilection for producing comparatively large pearls.
Pearls also come in many colours. The most popular colours are whites creams, and pinks. Silver, black, and gold are also gaining increasing interest. In fact, a deep lustrous black pearl is one of the rarest finds in the pearling industry, usually only being found in the South Sea near Australia. Thus, they can be one of the more costly items.
Historically, the world’s best pearls cane from the Persian Gulf, especially around what is now Bahrain. 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 l 930's with the discovery of large deposits of oil. Those who once dove for pearls sought prosperity in the economic boom ushered in by the oil industry. The water pollution resulting from spilled oil and indiscriminate over-fishing of oysters essentially ruined the once pristine pearl producing waters of the Gulf” Today; pearl diving is practiced only as a hobby. Still, Bahrain remains one of the foremost trading centres for high quality pearls. In fact, cultured pearls are banned from the Bahrain pearl market, in an effort to preserve the location's heritage.
Nowadays, pearls predominately come from Japan, Australia, Indonesia, Myanmar, China, India, Philippines, and Tahiti. Japan however, controls roughly 80% of the world pearl market, with Australia and China coming in second and third, respectivel1y.
Choose the most suitable headings for paragraphs B-1from the list of headings below. Write appropriate numbers (i-xii) in boxes f…8 on your answer sheet.
NB There are more headings than paragraphs, so you will not use them all.
List of Headings
I The importance of pearls in ancient time.
II The risk of pearl farming
III The mussels' life circle
IV Different types of pearls
V Irrelevance to water source
VI How pearls form naturally
VII Artificial pearls are not durable.
VII The most expensive colour
Ix Freshwater pearls are more valuable
X The difference between natural and cultured pearls
Xi Factors that determine the value
Xii Petroleum ruined pearl production