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Pearl

 
Pearl

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Pearl



 
 
A pearl is a hard, roundish object produced within the soft tissue (specifically the mantle
Mantle (mollusc)

The mantle is a significant part of the anatomy of molluscs: it is the dorsum body wall which covers the visceral mass.In many, but by no means all, species of molluscs, the Epidermis of the mantle secretes calcium carbonate and conchiolin, and creates a mollusc shell....
) of a living shelled mollusk. Just like the shell of mollusks, a pearl is made up of of calcium carbonate
Calcium carbonate

Calcium carbonate is a chemical compound with the chemical formula CalciumCarbonOxygen3. It is a common substance found as Rock in all parts of the world, and is the main component of seashells, snails, and eggshells....
 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 (baroque pearl
Baroque pearl

Baroque pearls are simply pearls that have an irregular shape. Cultured freshwater pearls are most commonly baroque, because freshwater pearls are mantle-tissue nucleated instead of bead nucleated....
s) occur. The finest quality natural pearls have been highly valued as gemstone
Gemstone

A gemstone or gem, also called a precious or semi-precious stone, is a piece of attractive mineral, which — when cut and polished — is used to make jewellery or other adornments....
s and objects of beauty
Beauty

Beauty is a characteristic of a person, Location , Object , or idea that provides a perception experience of pleasure, Value , or satisfaction....
 for many centuries, and because of this, the word pearl became a metaphor
Metaphor

Metaphor is language that directly compares seemingly unrelated subjects. It is a figure of speech that compares two or more things without using the words "like" or "as." More generally, a metaphor describes a first subject as being or equal to a second object in some way....
 for something very rare, very fine, very admirable and very valuable.

Valuable pearls occur in the wild, but they are very rare.






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A pearl is a hard, roundish object produced within the soft tissue (specifically the mantle
Mantle (mollusc)

The mantle is a significant part of the anatomy of molluscs: it is the dorsum body wall which covers the visceral mass.In many, but by no means all, species of molluscs, the Epidermis of the mantle secretes calcium carbonate and conchiolin, and creates a mollusc shell....
) of a living shelled mollusk. Just like the shell of mollusks, a pearl is made up of of calcium carbonate
Calcium carbonate

Calcium carbonate is a chemical compound with the chemical formula CalciumCarbonOxygen3. It is a common substance found as Rock in all parts of the world, and is the main component of seashells, snails, and eggshells....
 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 (baroque pearl
Baroque pearl

Baroque pearls are simply pearls that have an irregular shape. Cultured freshwater pearls are most commonly baroque, because freshwater pearls are mantle-tissue nucleated instead of bead nucleated....
s) occur. The finest quality natural pearls have been highly valued as gemstone
Gemstone

A gemstone or gem, also called a precious or semi-precious stone, is a piece of attractive mineral, which — when cut and polished — is used to make jewellery or other adornments....
s and objects of beauty
Beauty

Beauty is a characteristic of a person, Location , Object , or idea that provides a perception experience of pleasure, Value , or satisfaction....
 for many centuries, and because of this, the word pearl became a metaphor
Metaphor

Metaphor is language that directly compares seemingly unrelated subjects. It is a figure of speech that compares two or more things without using the words "like" or "as." More generally, a metaphor describes a first subject as being or equal to a second object in some way....
 for something very rare, very fine, very admirable and very valuable.

Valuable pearls occur in the wild, but they are very rare. Cultured or farmed pearls make up the majority of those that are currently sold. Pearls from the sea are valued more highly than freshwater pearls. Imitation or fake pearls are also widely sold in inexpensive jewelry, but the quality of the iridescence is usually very poor, and generally speaking, fake pearls are usually quite easy to distinguish from the real thing. Pearls have been harvested, or more recently cultivated, primarily for use in jewelry, but in the past they were also stitched onto lavish clothing, as worn, for example, by royalty. Pearls have also been crushed and used in cosmetics, medicines, or in paint formulations.

In several European languages, the word "pearl" is synonymous with "bead", which can lead to confusion during translation.

Definition of a pearl

Pearl
Almost any shelled mollusk can, by natural processes, produce some kind of "pearl" when an irritating microscopic object becomes trapped within the mollusk's mantle folds, but the great majority of these "pearls" are not valued as gemstones. Nacreous pearls, the best-known and most commercially-significant pearls, are primarily produced by two groups of molluscan bivalves or clam
Clam

Clam is a word which can be used for all, some, or only a few species of bivalve mollusks; the word is a common name which has no real Taxonomy significance in biology....
s. A nacreous pearl is made from layers of nacre
Nacre

Nacre, also known as mother of pearl, is an organic-inorganic composite material produced by some mollusks as an inner seashell layer. It is strong, resilient, and Iridescence....
, by the same living process as is used in the secretion of the mother of pearl which lines the shell.

A "natural pearl" is one that forms without any human intervention at all, in the wild, and is very rare. Many hundreds of pearl oysters or pearl mussels have to be gathered and opened, and thus killed, in order to find even one wild pearl, and for many centuries that was the only way pearls were obtained. This was the main reason why pearls fetched such extraordinary prices in the past. A cultured pearl
Cultured pearl

A cultured pearl is a pearl created by a pearl farmer under controlled conditions....
, on the other hand, is one that has been formed on a pearl farm. In modern times however, almost all the pearls for sale were formed with the aid of human pearl farmers. The great majority of pearls on the market are cultured pearls.

One family of nacreous pearl bivalves, the pearl oyster
Pearl oyster

Pinctada is a genus of pearl oysters. These are saltwater clams, Marine bivalve mollusks of the genus Pinctada in the family Pteriidae....
s, lives in the sea while the other, very different group of bivalves live in freshwater; these are the river mussel
Mussel

The common name mussel is used for members of several different families of clams or bivalve molluscs, from both saltwater and freshwater habitats....
s such as the freshwater pearl mussel
Freshwater pearl mussel

The freshwater pearl mussel, scientific name Margaritifera margaritifera, is an endangered species of freshwater mussel, an Aquatic animal bivalve mollusk in the family Margaritiferidae, the freshwater pearl mussels....
. Saltwater pearls can grow in several species of marine
Marine (ocean)

Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology....
 pearl oysters in the family
Family (biology)

In biological classification, family is a taxonomic rank. Exact details of formal nomenclature depend on the Nomenclature Codes which applies....
 Pteriidae
Pteriidae

Pteriidae is a family of medium-sized to large saltwater clams. They are pearl oysters, Marine bivalve mollusks in the order Pterioida.Some of the species in this family are important economically as the source of saltwater pearls....
. Freshwater pearls grow within certain (but by no means all) species of freshwater mussels in the order Unionida, the families Unionidae
Unionidae

Unionidae is a Family of freshwater mussels, aquatic animal bivalve mollusks which are sometimes known as river mussels, naiads or simply as unionids....
 and Margaritiferidae
Margaritiferidae

Margaritiferidae is a Family of medium-sized freshwater mussels, aquatic animal bivalve mollusks in the order Unionoida. They are known as freshwater pearl mussels, because they are capable of producing pearls....
.
Pearl Oysters

Physical properties

The unique luster
Lustre (mineralogy)

Lustre is a description of the way light interacts with the surface of a crystal, rock , or mineral. For example, a diamond is said to have an adamantine lustre and pyrite is said to have a metallic lustre....
 of pearls depends upon the reflection
Reflection (physics)

Reflection is the change in direction of a wavefront at an wiktionary:interface between two differentmedium so that the wavefront returns into the medium from which it originated....
, refraction
Refraction

Refraction is the change in direction of a wave due to a change in its speed. This is most commonly observed when a wave passes from one optical medium to another....
, and diffraction
Diffraction

Diffraction is normally taken to refer to various phenomena which occur when a wave encounters an obstacle. It is described as the apparent bending of waves around small obstacles and the spreading out of waves past small openings....
 of light from the translucent layers. The thinner and more numerous the layers in the pearl, the finer the luster. The iridescence
Iridescence

Iridescence is an optical phenomenon in which hue changes with the angle from which a surface is viewed. Iridescence may be easily seen in soap bubbles and butterfly wings....
 that pearls display is caused by the overlapping of successive layers, which breaks up light falling on the surface.

In addition, pearls (especially cultured freshwater pearls) can be dyed yellow, green, blue, brown, pink, purple, or black.

Freshwater and saltwater pearls


Freshwater and saltwater pearls may sometimes look quite similar, but they come from very different sources.

Natural freshwater pearls form in various species of freshwater mussels, family Unionidae
Unionidae

Unionidae is a Family of freshwater mussels, aquatic animal bivalve mollusks which are sometimes known as river mussels, naiads or simply as unionids....
, which live in lakes, rivers, ponds and other bodies of fresh water. These freshwater pearl mussels occur not only in hotter climates, but also in colder more temperate areas such as Scotland
Scotland

conventional_long_name = ScotlandAlba|common_name= Scotland|image_flag = Flag of Scotland.svg|flag_width = 130px...
: see the freshwater pearl mussel
Freshwater pearl mussel

The freshwater pearl mussel, scientific name Margaritifera margaritifera, is an endangered species of freshwater mussel, an Aquatic animal bivalve mollusk in the family Margaritiferidae, the freshwater pearl mussels....
. However, most freshwater cultured pearls sold today come from China.

Saltwater pearls grow within pearl oysters, family Pteriidae
Pteriidae

Pteriidae is a family of medium-sized to large saltwater clams. They are pearl oysters, Marine bivalve mollusks in the order Pterioida.Some of the species in this family are important economically as the source of saltwater pearls....
, which live in oceans. Saltwater pearl oysters are usually cultivated in protected lagoon
Lagoon

A lagoon is a body of comparatively shallow sea water or brackish water separated from the deeper sea by a shallow or exposed Bar , reef, or similar feature....
s or volcanic atolls.

Creation of a pearl

The difference between natural and cultured pearls focuses on whether the pearl was created spontaneously by nature — without human intervention — or with human aid. Pearls are formed inside the shell of certain mollusks: as a defense mechanism to a potentially threatening irritant such as a parasite inside its shell, the mollusk creates a pearl to seal off the irritation.

The mantle of the mollusk deposits layers of calcium carbonate
Calcium carbonate

Calcium carbonate is a chemical compound with the chemical formula CalciumCarbonOxygen3. It is a common substance found as Rock in all parts of the world, and is the main component of seashells, snails, and eggshells....
 (CaCO3) in the form of the mineral
Mineral

A mineral is a naturally occurring solid formed through Geology processes that has a characteristic chemical composition, a highly ordered atomic structure, and specific physical properties....
 aragonite
Aragonite

Aragonite is a carbonate mineral, one of the two common, naturally occurring polymorphism of calcium carbonate, calciumcarbonoxygen3....
 or a mixture of aragonite and calcite
Calcite

Calcite is a Carbonate minerals and the most stable Polymorphism of calcium carbonate . The other polymorphs are the minerals aragonite and vaterite....
 (both crystalline forms of calcium carbonate) held together by an organic horn-like compound called conchiolin
Conchiolin

Conchiolin and perlucin are complex proteins which are secreted by a mollusc's outer epithelium .These proteins are part of a matrix of organic macromolecules, mainly proteins and polysaccharides, that assembled together form the microenvironment where crystals nucleate and grow....
. The combination of aragonite and conchiolin is called nacre
Nacre

Nacre, also known as mother of pearl, is an organic-inorganic composite material produced by some mollusks as an inner seashell layer. It is strong, resilient, and Iridescence....
, which makes up mother-of-pearl. The commonly held belief that a grain of sand acts as the irritant is in fact rarely the case. Typical stimuli include organic material, parasites, or even damage that displaces mantle tissue to another part of the animal's body. These small particles or organisms enter the animal when the shell valves are open for feeding or respiration. In cultured pearls, the irritant is typically a cut piece of the mantle epithelium, together with processed shell beads, the combination of which the animal accepts into its body.

Natural pearls

Natural pearls are nearly 100% calcium carbonate and conchiolin. It is thought that natural pearls form under a set of accidental conditions when a microscopic intruder or parasite enters a bivalve mollusk, and settles inside the shell. The mollusk, being irritated by the intruder, secretes the calcium carbonate and conchiolin to cover the irritant. This secretion process is repeated many times, thus producing a pearl. Natural pearls come in many shapes, with perfectly round ones being comparatively rare.

Cultured pearls

Pearls
Cultured pearls (nucleated and non-nucleated or tissue nucleated cultured pearls) and imitation pearls can be distinguished from natural pearls by X-ray examination. Nucleated cultured pearls are often 'pre-formed' as they tend to follow the shape of the implanted shell bead nucleus. Once the pre-formed beads are inserted into the oyster, it secretes a few layers of nacre around the outside surface of the implant before it is removed after six months or more.

When a nucleated cultured pearl is X-rayed, it reveals a different structure to that of a natural pearl. A cultured pearl shows a solid center with no concentric growth rings, whereas a natural pearl shows a series of concentric growth rings.

Gemological identification

A well equipped gem testing laboratory (e.g. SSEF, Guebelin, GIA, AGTA) is able to distinguish natural pearls from cultured pearls by using a gemological x-ray
X-ray

X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 10 to 0.01 nanometers, corresponding to frequency in the range 30 Hertz to 30 Hertz and energies in the range 120 Electron volt to 120 keV....
 in order to examine the center of a pearl. With an x-ray it is possible to see the growth rings of the pearl, where the layers of calcium carbonate are separated by thin layers of conchiolin. The differentiation of natural pearls from tissue-nucleated cultured pearls can be very difficult without the use of this x-ray technique.

Natural and cultured pearls can be distinguished from imitation pearls using a microscope
Microscope

A microscope is an Laboratory equipment for viewing objects that are too small to be seen by the naked or unaided eye. The science of investigating small objects using such an instrument is called microscopy....
. Another method of testing for imitations is to rub the pearl against the surface of a front tooth. Imitation pearls are completely smooth, but natural and cultured pearls are composed of nacre platelets, which feel slightly gritty.

Value of a natural pearl

Quality natural pearls are very rare jewels. The actual value of a natural pearl is determined in the same way as it would be for other "precious" gems. The valuation factors include size, shape, quality of surface, orient and luster.

Single natural pearls are often sold as a collector's item, or set as centerpieces in unique jewelry. Very few matched strands of natural pearls exist, and those that do often sell for hundreds of thousands of dollars. Yachtsman and financier Cartier purchased the landmark Cartier store on Fifth Avenue in New York for $100 cash and a double strand of matched natural pearls valued at $1 million.

Keshi pearls, although they often occur by chance, are not considered natural pearls. They are a byproduct of the culturing process, and hence do not happen without human intervention. These pearls are quite small: typically a few millimeters in size. Keshi pearls are produced by many different types of marine mollusks and freshwater mussels in China. Today many "keshi" pearls are actually intentional, with post-harvest shells returned to the water to regenerate a pearl in the existing pearl sac.

Origin of a natural pearl

Previously natural pearls were found in many parts of the world. Present day natural pearling is confined mostly to seas off Bahrain
Bahrain

The Kingdom of Bahrain, in , , literally Kingdom of the Two Seas).Bahrain is an Arabic island country in the Persian Gulf ruled by the Al Khalifa regime....
. Australia also has one of the world's last remaining fleets of pearl diving ships. Australian pearl divers dive for south sea pearl oysters to be used in the cultured south sea pearl industry. The catch of pearl oysters is similar to the numbers of oysters taken during the natural pearl days. Hence significant numbers of natural pearls are still found in the Australian Indian Ocean waters from wild oysters. X-Ray examination is required to positively verify natural pearls found today.

Different types of cultured pearls, including black pearls

Black pearls, frequently referred to as Black Tahitian Pearls, are highly valued because of their rarity; the culturing process for them dictates a smaller volume output and can never be mass produced. This is due to bad health and/or non-survival of the process, rejection of the nucleus and their sensitivity to changing climatic and ocean conditions. Before the days of cultured pearls, black pearls were rare and highly valued for the simple reason that white pearl oysters rarely produced naturally black pearls, and black pearl oysters rarely produced any natural pearls at all.

Since the development of pearl culture technology, the black pearl oyster found in Tahiti and many other Pacific Island areas has been extensively used for producing cultured pearls. The rarity of the black cultured pearl is now a "comparative" issue. The black cultured pearl is rare when compared to Chinese freshwater cultured pearls, and Japanese and Chinese akoya cultured pearls, and is more valuable than these pearls. However, it is more abundant than the South Sea pearl, which is more valuable than the black cultured pearl. This is simply because the black pearl oyster Pinctada margaritifera is far more abundant than the elusive, rare, and larger south sea pearl oyster - Pinctada maxima, which cannot be found in lagoons, but which must be dived for in a rare number of deep ocean habitats or grown in hatcheries.

Black cultured pearls from the black pearl oyster — Pinctada margaritifera — are not South Sea pearls, although they are often mistakenly described as black South Sea pearls. In the absence of an official definition for the pearl from the black oyster, these pearls are usually referred to as "black Tahitian pearls".

The correct definition of a South Sea pearl — as described by CIBJO and the GIA — is a pearl produced by the Pinctada maxima pearl oyster. South Sea pearls are the color of their host Pinctada maxima oyster — and can be white, silver, pink, gold, cream, and any combination of these basic colors, including overtones of the various colors of the rainbow displayed in the pearl nacre of the oyster shell itself.

Pearls and calcareous concretions from other species

Biologically speaking, under the right set of circumstances, almost any shelled mollusk can produce some kind of pearl, however, most of these molluscan pearls have no luster or iridescence. The great majority of mollusk species produce pearls which are not attractive to look at, and are sometimes not even very durable, such that they usually have no value at all, except perhaps to a scientist, a collector, or as a curiosity. These objects used to be referred to as "calcareous concretions" by some gemologists, even though a malacologist would still consider them to be pearls. Valueless pearls of this type are sometimes found in edible mussel
Mussel

The common name mussel is used for members of several different families of clams or bivalve molluscs, from both saltwater and freshwater habitats....
s, edible oyster
Oyster

The common name oyster is used for a number of different groups of bivalve mollusks, most of which live in marine habitats or brackish water....
s, escargot snails, and so on. Kenneth Scarrat, director of GIA Bangkok, has recently argued for changes to current nomenclature. He argues conch "pearls" should be referred to (and various other types of mollusc pearls) as simply pearls, not "calcareous concretions".

A few species produce pearls that can be of interest as gemstones. These species include the bailer shell Melo (genus)
Melo (genus)

Melo is a genus of extremely large sea snails, marine gastropod molluscs in the family Volutidae, the volutes.Species in this genus sometimes produce large pearls, "calcareous concretions." The image in the taxobox shows a group of these pearls along with a shell of the species Melo melo....
, the giant clam
Giant clam

The giant clam, Tridacna gigas, or traditionally, pa?ua, is the largest living bivalve mollusk. One of a number of large clam species native to the shallow coral reefs of the South Pacific ocean and Indian oceans, they can weigh more than 200 kilograms , measure as much as 1.2 metres across, and have an average lifespan in the wild...
 Tridacna, various scallop
Scallop

A scallop is a Marine bivalve mollusk of the Family Pectinidae. Scallops are a wiktionary:cosmopolitan family, found in all of the world's oceans....
 species, Pen shells Pinna (genus)
Pinna (genus)

Pinna is a genus of pen shells. It is a cosmopolitan genus of bivalve molluscs characterized by elongated, wedge-shaped shells which most commonly stand point-first in the sea bottom in which they live, anchored by a net of byssus threads....
, and abalone
Abalone

Abalone are medium-sized to very large edible sea snails, marine gastropod mollusks in the family Haliotidae and the genus Haliotis....
s. Another example is the conch pearl (sometimes referred to simply as the 'pink pearl'), which is found very rarely growing between the mantle and the shell of the queen conch
Conch

A conch is one of a number of different species of medium-sized to large saltwater snails or their shells.True conchs are Marine gastropod molluscs in the family Strombidae, and the genus Strombus....
 or pink conch, Strombus gigas
Strombus gigas

Strombus gigas Linnaeus, 1758, now known as Eustrombus gigas, many common names including "queen conch" is a species of very large edible sea snail, a marine gastropod mollusk in the family Strombidae, the true conchs....
, a large sea snail or marine gastropod from the Caribbean Sea
Caribbean Sea

The Caribbean Sea is a sea of the Atlantic Ocean situated in the mid-latitudes of the Western Hemisphere, bounded to the south and west by the Americas, with the North Atlantic Ocean proper to the northeast and the Gulf of Mexico to the northwest....
. These pearls, which are often pink in color, are a by-product of the conch fishing industry, and the best of them display a shimmering optical effect related to chatoyance known as 'flame structure'.

Somewhat similar gastropod pearls, this time more orange in hue, are (again very rarely) found in the horse conch Pleuroploca gigantea
Pleuroploca gigantea

Pleuroploca gigantea, common name the horse conch, is a species of extremely large predatory subtropical and tropical sea snail, a marine gastropod mollusk in the family Fasciolariidae, the spindle snails, tulip snails and their allies....
.

The largest pearl known, was found in the Philippines
Philippines

The Philippines, officially known as the Republic of the Philippines, is a country in Southeast Asia with Manila as its capital city. It comprises 7,107 islands in the western Pacific Ocean....
 in 1934. It is a naturally-occurring, non-nacreous, calcareous concretion from a giant clam
Giant clam

The giant clam, Tridacna gigas, or traditionally, pa?ua, is the largest living bivalve mollusk. One of a number of large clam species native to the shallow coral reefs of the South Pacific ocean and Indian oceans, they can weigh more than 200 kilograms , measure as much as 1.2 metres across, and have an average lifespan in the wild...
. Because it did not grow in a pearl oyster it is not pearly, instead it has a porcellaneous surface. In other words, it is glossy like a china plate. Other pearls from giant clams are known to exist, but this is a particularly large one. The pearl weighs 14 lb (6.4 kg) and was supposedly first discovered by an anonymous Filipino Muslim diver off the island of Palawan
Palawan

Palawan is an island province of the Philippines located in the MIMAROPA Regions of the Philippines. Its capital is Puerto Princesa City, and it is the largest province in the country in terms of total area of jurisdiction....
 in 1934. According to the legend as it is currently told, a Palawan chieftain gave the pearl to Wilbur Dowell Cobb in 1936 as a gift for having saved the life of his son. The pearl had been named the "Pearl of Allah" by the Muslim tribal chief, because it resembled a turbaned head. Another even more elaborate legend says that this object is actually the Pearl of Lao-Tzu
Pearl of Lao Tzu

The Pearl of Laozi is the largest known "pearl" in the world. It is not a gem quality pearl, but is instead what is known as a clam "pearl" or Tridacna "pearl" from a giant clam....
, a cultured pearl created with a carved amulet and then supposedly progressively grafted into several giant clams, before supposedly being lost due to a shipwreck in 1745. This legend has been discredited, however because this pearl is indeed the product of a giant clam, Tridacna gigas, which cannot be grafted. The pearl is also a whole pearl, not a mabe pearl, and whole pearl culturing technology is only 100 years old.

The history of pearl hunting and pearl farming


Pearl hunting

For thousands of years, most seawater pearls were retrieved by divers working in the Indian Ocean
Indian Ocean

The Indian Ocean is the third largest of the world's oceanic divisions, covering about 20% of the water on the Earth's surface. It is bounded on the north by Asia ; on the west by Africa; on the east by Indochina, the Sunda Islands, and Australia; and on the south by the Southern Ocean ....
, in areas like the Persian Gulf, the Red Sea, and in the Gulf of Mannar.

Starting in the Han Dynasty
Han Dynasty

The Han Dynasty followed the Qin Dynasty and preceded the Three Kingdoms in China. The Han Dynasty was ruled by the family known as the Liu clan who had peasant origins....
 (206 BC - 220 AD), the Chinese
China

China is a Culture of China, an ancient civilization, and, depending on perspective, a national or multinational entity extending over a large area in East Asia....
 hunted extensively for seawater pearls in the South China Sea
South China Sea

The South China Sea is a marginal sea*south of China,*west of the Philippines,*north west of Sabah , Sarawak and Brunei,*north of Indonesia,...
.

When Spanish conquistadors arrived in the Western Hemisphere, they discovered that around the islands of Cubagua
Cubagua

Cubagua or Isla de Cubagua is the smallest and least populated of the three islands constituting the Venezuelan state of Nueva Esparta, after Isla Margarita and Coche, Venezuela....
 and Margarita
Isla Margarita

Margarita Island is the largest island of the Nueva Esparta States of Venezuela in Venezuela, situated in the Caribbean Sea, off the northeastern coast of the country....
, some 200 km north of the Venezuelan coast, was an extensive pearl bed. One discovered and named pearl, La Peregrina, was offered to the Spanish queen. According to Garcilasso de la Vega, who says that he saw La Peregrina at Seville in 1507, (Garcilasso, "Historie des Incas, Rois du Perou," Amsterdam, 1704, Vol. II, P. 352.) this was found at Panama in 1560 by a negro who was rewarded with his liberty, and his owner with the office of alcalde of Panama.

Margarita pearls are extremely difficult to find today and are known for their unique yellowish color. The most famous Margarita necklace that any one can see today is the one that then Venezuelan President Romulo Betancourt
Rómulo Betancourt

R?mulo Ernesto Betancourt Bello , "The Father of Venezuelan Democracy", was President of Venezuela of Venezuela from 1945 to 1948 and again from 1959 to 1964, as well as leader of Accion Democratica - Venezuela's dominant political party in the 20th century....
 gave to Jacqueline Kennedy when she and her husband, President John F. Kennedy
John F. Kennedy

John Fitzgerald "Jack" Kennedy , often referred to by his initials JFK, was the List of Presidents of the United States President of the United States, serving from 1961 until John F....
 paid an official visit to Venezuela.

Before the beginning of the 20th Century, pearl hunting
Pearl hunting

Pearl hunting or pearl diving refers to a now largely obsolete method of retrieving pearls from pearl oysters, freshwater pearl mussels and, on rare occasions, other nacre-producing creatures, such as abalone....
 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 mussels and oysters produce pearls. In a haul of three tons, only three or four oysters will produce perfect pearls .

The development of pearl farming

Today, almost all pearls used for jewelry are cultured by planting a core or nucleus into pearl oyster
Pearl oyster

Pinctada is a genus of pearl oysters. These are saltwater clams, Marine bivalve mollusks of the genus Pinctada in the family Pteriidae....
s. The pearls are usually harvested after one year for akoya, 2-4 years for Tahitian and South Sea, and 2-7 years for freshwater. This perliculture process was first developed by William Sawville-Kent who passed the information along to Tatsuhei Mise and Tokichi Nishikawa from Japan
Japan

Japan is an island country in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, People's Republic of China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south....
.

The nucleus is generally a polished bead made from freshwater mussel
Mussel

The common name mussel is used for members of several different families of clams or bivalve molluscs, from both saltwater and freshwater habitats....
 shell. Along with a small piece of mantle tissue from another mollusk to serve as a catalyst for the pearl sac, it is surgically implanted into the gonad (reproductive organ) of a saltwater mollusk. In freshwater perliculture, only the piece of tissue is used in most cases, and is inserted into the fleshy mantle of the host mussel. South Sea and Tahitian pearl oysters, also known as Pinctada maxima and Pinctada margaritifera, 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 2-3 years of growth.
White Pearl Necklace
Despite the common misperception, Mikimoto did not discover the process of pearl culture. The accepted process of pearl culture was developed by William Sawville-Kent in Australia and brought to Japan by Tokichi Nishikawa and Tatsuhei Mise. Nishikawa was granted the patent in 1916, and married the daughter of Mikimoto. Mikimoto was able to use Nishikawa's technology. After the patent was granted in 1916, the technology was immediately commercially applied to akoya pearl oysters in Japan in 1916. Mise's brother was the first to produce a commercial crop of pearls in the akoya oyster. Mitsubishi's Baron Iwasaki immediately applied the technology to the south sea pearl oyster in 1917 in the Philippines, and later in Buton, and Palau. Mitsubishi was the first to produce a cultured south sea pearl - although it was not until 1928 that the first small commercial crop of pearls was successfully produced.

The original Japanese cultured pearls, known as akoya pearls, are produced by a species of small pearl oyster, Pinctada fucata martensii, which is no bigger than 6 to 8 cm in size, hence akoya pearls larger than 10 mm in diameter are extremely rare and highly prized. Today, a hybrid mollusk is used in both Japan and China in the production of akoya pearls. It is a cross between the original Japanese species, and the Chinese species Pinctada chemnitzii.

Recent pearl production

China has recently overtaken Japan in akoya pearl production. Japan has all but ceased its production of akoya pearls smaller than 8 mm. Japan maintains its status as a pearl processing center, however, and imports the majority of Chinese akoya pearl production. These pearls are then processed (often simply matched and sorted), relabeled as product of Japan, and exported.

In the past couple of decades, cultured pearls have been produced using larger oysters in the south Pacific
Pacific Ocean

The Pacific Ocean is the largest of the Earth's oceanic divisions. Its name is derived from the Latin name Mare Pacificum, "peaceful sea", bestowed upon it by the Portugal explorer Ferdinand Magellan....
 and Indian Ocean
Indian Ocean

The Indian Ocean is the third largest of the world's oceanic divisions, covering about 20% of the water on the Earth's surface. It is bounded on the north by Asia ; on the west by Africa; on the east by Indochina, the Sunda Islands, and Australia; and on the south by the Southern Ocean ....
. The largest pearl oyster is the Pinctada maxima, which is roughly the size of a dinner plate. South Sea pearls are characterized by their large size and warm luster. Sizes up to 14 mm in diameter are not uncommon. South Sea pearls are primarily produced in Australia
Australia

Australia, officially the Commonwealth of Australia, is a country in the southern hemisphere comprising the Australia of the world's smallest continent, the major island of Tasmania, and numerous list of islands of Australia in the Indian Ocean and Pacific Oceans....
, Indonesia
Indonesia

The Republic of Indonesia , is a transcontinental country in Southeast Asia and Oceania. Comprising Islands of Indonesia, it is the world's largest Archipelago state....
 and the Philippines.

Mitsubishi commenced pearl culture with the south sea pearl oyster in 1916, as soon as the technology patent was commercialized. By 1931 this project was showing signs of success, but was upset by the death of Tatsuhei Mise. Although the project was recommenced after Tatsuhei's death, the project was discontinued at the beginning of WWII before significant productions of pearls were achieved.

After WWII, new south sea pearl projects were commenced in the early 1950s in Burma and Kuri Bay
Kuri Bay

Kuri Bay is a remote coastal bay in the far north of Western Australia in the Kimberley region, about 370 km north of Broome, Western Australia....
 and Port Essington in Australia. Japanese companies were involved in all projects using technicians from the original Mitsubishi south sea pre-war projects.

Japanese freshwater pearl farming

In 1914, pearl farmers began growing cultured freshwater pearls using the pearl mussels native to Lake Biwa
Lake Biwa

, formerly known as Omi Lake, is the largest freshwater lake in Japan, located in Shiga Prefecture , northeast of the former capital city of Kyoto....
. This lake, the largest and most ancient in Japan, lies near the city of Kyoto
Kyoto

Sorry, no overview for this topic
. The extensive and successful use of the Biwa Pearl Mussel is reflected in the name Biwa pearls, a phrase which was at one time nearly synonymous with freshwater pearls in general. Since the time of peak production in 1971, when Biwa pearl farmers produced six tons of cultured pearls, pollution has caused the virtual extinction of the industry. Japanese pearl farmers recently cultured a hybrid pearl mussel — a cross between Biwa Pearl Mussels and a closely related species from China, Hyriopsis cumingi, in Lake Kasumigaura
Lake Kasumigaura

is the list of lakes in Japan lake in Japan, located 60 km to the north-east of tokyo. Lake Kasumigaura is actually the name given to a group of contiguous lakes, which includes the main lake, Nishiura , and two smaller lakes, Kitaura ...
. This industry has also nearly ceased production, due to pollution.

Japanese pearl producers also invested in producing cultured pearls with freshwater mussel
Mussel

The common name mussel is used for members of several different families of clams or bivalve molluscs, from both saltwater and freshwater habitats....
s in the region of Shanghai, China
China

China is a Culture of China, an ancient civilization, and, depending on perspective, a national or multinational entity extending over a large area in East Asia....
. China has since become the world's largest producer of freshwater pearls, producing more than 1,500 metric tons per year.

Led by pearl pioneer John Latendresse
John Latendresse

John Latendresse is known for being the "father of American cultured freshwater pearls". He was the first successful North American freshwater pearl farmer and was voted one of the pearl industry's most important people of the century....
 and his wife Chessy, the United States began farming cultured freshwater pearls in the mid 1960's. National Geographic Magazine introduced the American cultured pearl as a commercial product in their August 1985 issue. The Tennessee pearl farm has emerged as a tourist destination in recent years, but commercial production of freshwater pearls has ceased.

Pearls in 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.

Shapes

Jan Vermeer Van Delft 007
Pearls come in eight basic shapes: round, semi-round, button, drop, pear, oval, baroque, and circled. Perfectly round pearls are the rarest and most valuable shape. 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 earrings where the back half of the pearl is covered, making it look like a larger, round pearl.

Jan Vermeer Van Delft 008
Drop and pear shaped pearls are sometimes referred 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. Circled pearls are characterized by concentric ridges, or rings, around the body of the pearl.

In general, cultured pearls are less valuable than natural pearls, and imitation pearls are less valuable than cultured pearls. One way that jewelers can determine whether a pearl is cultured or natural is to have a gem lab perform an x-ray of the pearl. If the x-ray reveals a nucleus, the pearl is likely a bead-nucleated saltwater pearl. If no nucleus is present, but irregular and small dark inner spots indicating a cavity are visible, combined with concentric rings of organic substance, the pearl is likely a cultured freshwater. Cultured freshwater pearls can often be confused for natural pearls which present as homogeneous pictures which continuously darken toward the surface of the pearl. Natural pearls will often show larger cavities where organic matter has dried out and decomposed.

Some imitation pearls are simply made of mother-of-pearl, coral
Coral

Corals are marine organisms from the class Anthozoa and exist as small sea anemone?like polyps, typically in colonies of many identical individuals....
 or conch
Conch

A conch is one of a number of different species of medium-sized to large saltwater snails or their shells.True conchs are Marine gastropod molluscs in the family Strombidae, and the genus Strombus....
 shell, 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.

Lengths of pearl necklaces


There is a special vocabulary used to describe the length of pearl necklaces. While most other necklaces are simply referred to by their physical measurement, pearl necklaces are named by how low they hang when worn around the neck. A collar, measuring 10 to 13 inches or 25 to 33 cm in length, sits directly against the throat and does not hang down the neck at all; collars are often made up of multiple strands of pearls. Pearl chokers, measuring 14 to 16 inches or 35 to 41 cm in length, nestle just at the base of the neck. A strand called a princess length, measuring 17 to 19 inches or 43 to 48 cm in length, comes down to or just below the collarbone. A matinee length, measuring 20 to 24 inches or 50 to 60 cm in length, falls just above the breasts. An opera length, measuring 28 to 35 inches or 70 to 90 cm in length, will be long enough to reach the breastbone or sternum of the wearer; and longer still, a pearl rope, measuring more than 45 inches or 115 cm in length, is any length that falls down farther than an opera.

Necklaces can also be classified as uniform, or graduated. In a uniform strand of pearls, all pearls are classified as the same size, but actually fall in a range. A uniform strand of akoya pearls, for example, will measure within 0.5 mm. So a strand will never be 7 mm, but will be 6.5-7 mm. Freshwater pearls, Tahitian pearls, and South Sea pearls all measure to a full millimeter when considered uniform.

A graduated strand of pearls most often has at least 3 mm of differentiation from the ends to the center of the necklace. Popularized in the United States
United States

The United States of America is a Federal government constitutional republic comprising U.S. state and a federal district. The country is situated mostly in central North America, where its Contiguous United States and Washington, D.C., the Capital districts and territories, lie between the Pacific Ocean and Atlantic Oceans, Borders of the U...
 during the 1950s by the GIs bringing strands of cultured akoya pearls home from Japan
Japan

Japan is an island country in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, People's Republic of China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south....
, a 3.5 momme, 3 mm to 7 mm graduated strand was much more affordable than a uniform strand because most of the pearls were small.

Colors of pearl jewelry

Earrings and necklaces can also be classified on the grade of the color of the pearl. While white, and more recently black, saltwater pearls are by far the most popular, other color tints can be found on pearls from the oceans. Pink, blue, champagne, green and even purple saltwater pearls can be encountered, but to collect enough pearls to form a complete string of the same size and same shade can take years.

Religious references


Hebrew Scriptures

According to Rebbenu Bachya
Bahya ben Asher

Bahye ben Asher or Bahye ben Asher ben Halawa also known as the Rabbeinu Behaye, born about the middle of the thirteenth century at Saragossa, died 1340, was a 13th century rabbi and scholar of Judaism....
, the word Yahalom in the verse Exodus
Exodus

Exodus is the second book of the Jewish Torah and of the Christian Old Testament. It tells how Moses leads the Israelites out of Egypt and through the wilderness to the Mountain of God Sinai....
 28:18 means "pearl" and was the stone on the Hoshen
Hoshen

Hoshen/Choshen is a Hebrew language word usually translated as breastplate; in English language contexts it refers to a specific breastplate – the sacred breastplate worn by the King James Bible or Torah), according to the Book of Exodus....
 representing the tribe of Zebulun
Zebulun

Zebulun was, according to the Books of Book of Genesis and Book of Numbers, the sixth son of Jacob and Leah, and the founder of the Israelites of Tribe of Zebulun....
. This is generally disputed among scholars, particularly since the word in question in most manuscripts is actually Yasepheh - the word from which jasper
Jasper

Jasper is an Opacity , impure variety of silica, usually red, yellow or brown in color. This mineral breaks with a smooth surface, and is used for ornamentation or as a gemstone....
 derives; scholars think that refers to green jasper (the rarest and most prized form in early times) rather than red jasper (the most common form). Yahalom is usually translated by the Septuagint
Septuagint

The Septuagint , or simply "LXX", is the Koine Greek version of the Hebrew Bible, translated in stages between the 3rd century BC and 1st century BC in Alexandria....
 as an "onyx
Onyx

Onyx is a cryptocrystalline form of quartz. The colors of its bands range from white to almost every color . Commonly, specimens of onyx available contain bands of colors of white, tan, and brown....
", but sometimes as "beryl
Beryl

The mineral beryl is a beryllium aluminium Silicate minerals#Cyclosilicates with the chemical formula Be3Al26. The hexagonal crystals of beryl may be very small or range to several meters in size....
" or as "jasper"; onyx only started being mined after the Septuagint was written, so the Septuagint's term "onyx" probably does not mean onyx - onyx is originally an Assyrian
Assyrian

Assyrian may refer to:in antiquity:*ancient Assyria**the Old Assyrian period **the Middle Assyrian period **the Neo-Assyrian period *Assyria , a province of the Achaemenid Empire...
 word meaning ring, and so could refer to anything used for making rings. Yahalom is similar to a Hebrew word meaning hit hard, so some people think that it means diamond. The variation in possibilities of meaning for this sixth stone in the Hoshen is reflected in different translations of the Bible — the King James Version translates the sixth stone as diamond
Diamond

In mineralogy, diamond is the Allotropes of carbon where the carbon atoms are arranged in an isometric-hexoctahedral crystal lattice. After graphite, diamond is the second most stable form of carbon....
, the New International Version
New International Version

The New International Version is an English language translation of the Christianity Bible. Published by Zondervan, it became one of the most popular modern translations made in the twentieth century....
 translates it as emerald
Emerald

Emeralds are a variety of the mineral beryl colored green by trace amounts of chromium and sometimes vanadium. Beryl has a Hardness of 7.5 - 8 on the 10 point Mohs scale of mineral hardness....
, and the Vulgate
Vulgate

The Vulgate is an early Fifth Century version of the Bible in Latin, and largely the result of the labors of Jerome, who was commissioned by Pope Damasus I in 382 to make a revision of Vetus Latina....
 translates it as jaspis — meaning jasper. There is a wide range of views among traditional sources about which tribe the stone refers to.

Christian Scriptures

In a Christian
Christianity

Christianity is a Monotheistic religion #Christian view religion centered on the life and teachings of Jesus as New Testament view on Jesus' life....
 New Testament
New Testament

The New Testament is the name given to the second major division of the Christianity Bible, the first such division being the much longer Old Testament....
 parable
Parable

A parable is a brief, succinct story, in prose or Verse , that illustrates a moral or religious lesson. It differs from a fable in that fables use animals, plants, inanimate objects, and forces of nature as characters, while parables generally feature human characters....
, Jesus
Jesus

Jesus of Nazareth , also known as Jesus Christ, is the central figure of Christianity and is revered by most Christian churches as the Son of God and the Incarnation ....
 compared the Kingdom of Heaven
Kingdom of Heaven

Kingdom of Heaven may refer to:* Kingdom of God* Kingdom of Heaven , a 2005 film, directed by Ridley Scott...
 to a "pearl of great price"
Parable of the Pearl

The Parable of the Pearl or the Pearl of Great Price is a parable told by Jesus in explaining the value of the Kingdom of Heaven, according to Gospel of Matthew ....
 in Matthew 13: 45-46. "Again, the kingdom of heaven is like unto a merchant man, seeking goodly pearls: Who, when he had found one pearl of great price, went and sold all that he had, and bought it."

The language of symbolism was in common use around the time of Jesus Christ; most people were familiar with the symbolic meanings. The circle is a symbol of God because it has no beginning and no end. The circle or pearl was considered to represent Love, Knowledge (the combination of equal amounts of Love and Knowledge is a symbol of Wisdom, the 2 circles intertwined (owl eyes) is symbolic of Wisdom. Some other pearls are Truth, and Faith.

The twelve gates of the New Jerusalem are reportedly each made of a single pearl in Revelation
Book of Revelation

The Book of Revelation, also called Revelation to John, Apocalypse of John , and Revelation of Jesus Christ is the last Biblical canon of the New Testament in the Christian Bible....
 21:21, that is, the Pearly Gates
Pearly gates

The Pearly gates, in Christian beliefs, is an informal name for the gateway to Heaven, inspired by the description of the New Jerusalem in Book of Revelation 21:21— The twelve gates were twelve pearls, each gate being made from a single pearl....
. "And the twelve gates were twelve pearls; every gate was of one pearl: and the streets of the city were pure gold, as if transparent glass."

Holy things are compared to pearls in Matthew 7:6. "Give not that which is holy unto the dogs, neither cast ye your pearls before swine, lest they trample them under their feet, and turn again and rend you."

Pearls are also found in numerous references showing the wickedness and pride of a people, as in Revelation
Revelation

Revelation is the act of revealing or disclosing, or making something obvious and clearly understood through active or passive communication with the divinity....
 18:16. "And saying, Alas, alas, that great city, that was clothed in fine linen, and purple, and scarlet, and decked with gold, and precious stones, and pearls!"

The metaphor of a pearl appears in the longer Hymn of the Pearl, a poem respected for its high literary quality, and use of layered theological metaphor, found within one of the texts of Gnosticism
Gnosticism

Gnosticism refers to diverse, syncretistic religious movements in antiquity consisting of various belief systems generally united in the teaching that humans are divine souls trapped in a Nature created by an imperfect god, the demiurge; this being is frequently identified with the Abrahamic God, and is contrasted with a superior entity, ref...
.

The Pearl of Great Price is a book of scripture in The Church of Jesus Christ of Latter-day Saints.

Islamic references

The Qur'an
Qur'an

The Qur?an is the central religious text of Islam. Muslims believe the Qur?an to be the book of divine guidance and direction for mankind, and consider the original Arabic text to be the final revelation of God....
 often mentions that dwellers of paradise will be adorned with pearls:

22:23 God will admit those who believe and work righteous deeds, to Gardens beneath which rivers flow: they shall be adorned therein with bracelets of gold and pearls; and their garments there will be of silk.

35:33 Gardens of Eternity will they enter: therein will they be adorned with bracelets of gold and pearls; and their garments there will be of silk.

The handsome young boys in paradise are similarly depicted:

52:24 Round about them will serve, [devoted] to them, youths [handsome] as pearls well-guarded.

Hindu astrological belief in natural pearls

The Vedic
Historical Vedic religion

The religion of the Vedic period is the historical predecessor of Hinduism. Its liturgy is reflected in the Mantra portion of the four Vedas, which are compiled in Sanskrit....
 tradition describes the sacred Nine Pearls
Nine Pearls

The Nine Pearls, sometimes known as the Nava Moti, are a group of sacred gemstones described in the Vedas text known as the Garuda Purana.The nine are enumerated as the Oyster Pearl, Conch Pearl, Cobra Pearl, Boar Pearl, Elephant Pearl, Bamboo Pearl, Whale Pearl, Fish Pearl, and Cloud Pearl....
 which were first documented in the Garuda Purana
Garuda Purana

Garuda Purana is one of the Puranas which are part of the Hinduism body of texts known as smriti....
, one of the books of the Hindu holy text Atharvaveda
Atharvaveda

The Atharvaveda is a sacred text of Hinduism, and one of the four Vedas, often called the "fourth Veda".According to tradition, the Atharvaveda was mainly composed by two groups of rishis known as the Atharvanas and the Angirasa, hence its oldest name is ....
. Ayurveda contains references to pearl powder as a stimulant of digestion and to treat mental ailments. According to Marco Polo, the kings of Malabar (now known as the Coromandel Coast
Coromandel Coast

The Coromandel Coast is the name given to the southeastern coast of the Indian peninsula....
) wore a necklace of 104 rubies and 104 precious pearls which was given from one generation of kings to the next. The reason was that every king had to say 104 prayers every morning and every evening. At least until the beginning of the 20th century it was a Hindu custom to present a completely new, undrilled pearl and pierce it during the ceremony.

See also

  • Ammolite
    Ammolite

    Ammolite is a rare and valuable opal-like organic gemstone found primarily along the eastern slopes of the Rocky Mountains of the United States and Canada....
     — another organic gemstone formed primarily of fossil aragonite mollusk shells
  • Broome
    Broome, Western Australia

    Broome is a pearling and tourist town in the Kimberley region of Western Australia, 2200 km north of Perth, Western Australia. The year round population is approximately 14,436, growing to more than 45,000 per month during the tourist season....
    , a pearling town in Western Australia
  • The Pearl Fishers
  • Pearl hunting
    Pearl hunting

    Pearl hunting or pearl diving refers to a now largely obsolete method of retrieving pearls from pearl oysters, freshwater pearl mussels and, on rare occasions, other nacre-producing creatures, such as abalone....


External links

  • PBS Pearl History Special.
  • by Edwin Streeter
  • by George Frederick Kunz and Charles Hugh Stevenson


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