Pearls – The Birthstone of June – Part 8

Timeline of Pearl Production

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 at Kuri Bay and Port Essington in Australia, and Burma. Japanese companies were involved in all projects using technicians from the original Mitsubishi South Sea pre-war projects. Kuri Bay is now the location of one of the largest and most well-known pearl farms owned by Paspaley, the biggest producer of South Sea pearls in the world.

In 2010, China overtook 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 two decades, cultured pearls have been produced using larger oysters in the south Pacific and Indian 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. In 2013, Indonesia Pearl supplied 43 percent of South Sea Pearls international market. The other significant producers are Australia, Philippines, Myanmar and Malaysia.

Freshwater Pearl Farming

In 1914, pearl farmers began growing cultured freshwater pearls using the pearl mussels native to Lake Biwa. This lake, the largest and most ancient in Japan, lies near the city of Kyoto. 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. This industry has also nearly ceased production, due to pollution. Currently, the Belpearl company based out of Kobe, Japan continues to purchase the remaining Kasumiga-ura pearls.

Japanese pearl producers also invested in producing cultured pearls with freshwater mussels in the region of Shanghai, China. China has since become the world’s largest producer of freshwater pearls, producing more than 1,500 metric tons per year (in addition to metric measurements, Japanese units of measurement such as the kan and momme are sometimes encountered in the pearl industry).

Led by pearl pioneer John Latendresse and his wife Chessy, the United States began farming cultured freshwater pearls in the mid-1960s. 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.

Momme Weight

For many cultured pearl dealers and wholesalers, the preferred weight measure used for loose pearls and pearl strands is the momme. Momme is a weight measure used by the Japanese for centuries. Today, momme weight is still the standard unit of measure used by most pearl dealers to communicate with pearl producers and wholesalers. One momme corresponds to 1/1000 kan. Reluctant to give up tradition, the Japanese government formalized the kan measure in 1891 as being exactly 3.75 kilograms or 8.28 pounds. Hence, 1 momme = 3.75 grams or 3750 milligrams.

In the United States, during the 19th and 20th centuries, through trade with Japan in silk cloth the momme became a unit indicating the quality of silk cloth.

Though millimeter size range is typically the first factor in determining a cultured pearl necklace’s value, the momme weight of pearl necklace will allow the buyer to quickly determine if the necklace is properly proportioned. This is especially true when comparing the larger south sea and Tahitian pearl necklaces.

More information about Pearls in Part 9 of this series!

(Information from Wikipedia, the free encyclopedia)

Pearls – The Birthstone of June – Part 7

History

Pearl hunting

A 14th-century piece of clothing used by Kuwaiti divers searching for pearls in the Persian Gulf

The ancient chronicle Mahavamsa mentions the thriving pearl industry in the port of Oruwella in the Gulf of Mannar in Sri Lanka. It also records that eight varieties of pearls accompanied Prince Vijaya’s embassy to the Pandyan king as well as king Devanampiya Tissa’s embassy to Emperor Ashoka.  Pliny the Elder (23–79AD) praised the pearl fishery of the Gulf as most productive in the world.

For thousands of years, seawater pearls were retrieved by divers in the Indian Ocean in areas such as the Persian Gulf, the Red Sea and the Gulf of Mannar. Evidence also suggest a prehistoric origin to pearl diving in these regions. Starting in the Han Dynasty (206 BC–220 AD), the Chinese hunted extensively for seawater pearls in the South China Sea. Tanka pearl divers of twelfth century China attached ropes to their waists in order to be safely brought back up to the surface.

When Spanish conquistadors arrived in the Western Hemisphere, they discovered that around the islands of Cubagua and Margarita, some 200 km north of the Venezuelan coast, was an extensive pearl bed (a bed of pearl oysters). One discovered and named pearl, La Peregrina pearl, was offered to Philip II of Spain and then gifted to his wife Mary I of England. According to Garcilasso de la Vega, who says that he saw La Peregrina at Seville in 1607, this was found at Panama in 1560 by a slave worker 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 anyone can see today is the one that then Venezuelan President Romulo Betancourt gave to Jacqueline Kennedy when she and her husband, President John F. Kennedy paid an official visit to Venezuela.

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 mussels and oysters produce pearls. In a haul of three tons, only three or four oysters will produce perfect pearls.

British Isles

Pearls were one of the attractions which drew Julius Caesar to Britain. They are, for the most part, freshwater pearls from mussels. Pearling was banned in the U.K. in 1998 due to the endangered status of river mussels. Discovery and publicity about the sale for a substantial sum of the Abernethy pearl in the River Tay had resulted in heavy exploitation of mussel colonies during the 1970s and 80s by weekend warriors. When it was permitted it was carried on mainly by Scottish Travellers who found pearls varied from river to river with the River Oykel in the Highlands being noted for the finest rose-pink pearls. There are two firms in Scotland that are licensed to sell pre-1998 freshwater pearls.

Pearl farming

A pearl being extracted from an akoya pearl oyster. See also: Oyster farming

Today, the cultured pearls on the market can be divided into two categories. The first category covers the beaded cultured pearls, including akoya, South Sea and Tahiti. These pearls are gonad grown, and usually one pearl is grown at a time. This limits the number of pearls at a harvest period. 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 the British biologist William Saville-Kent who passed the information along to Tatsuhei Mise and Tokichi Nishikawa from Japan. The second category includes the non-beaded freshwater cultured pearls, like the Biwa or Chinese pearls. As they grow in the mantle, where on each wing up to 25 grafts can be implanted, these pearls are much more frequent and saturate the market completely. An impressive improvement in quality has taken place in the last ten years when the former rice-grain-shaped pebbles are compared with the near round pearls of today. In the last two years large near perfect round bead nucleated pearls up to 15mm in diameter have been produced with metallic luster.

The nucleus bead in a beaded cultured pearl is generally a polished sphere made from freshwater mussel shell. Along with a small piece of mantle tissue from another mollusk (donor shell) 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 beads as part of the same procedure and then returned to the water for another 2–3 years of growth.

Despite the common misperception, Mikimoto did not discover the process of pearl culture. The accepted process of pearl culture was developed by the British Biologist William Saville-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 (2.4 to 3.1 in) in size, hence akoya pearls larger than 10 mm in diameter are extremely rare and highly priced. Today, a hybrid mollusk is used in both Japan and China in the production of akoya pearls.

Cultured Pearls were sold in cans for the export market. These were packed in Japan by the I.C.P. Canning Factory (International Pearl Company L.T.D.) in Nagasaki Pref. Japan.

(Information from Wikipedia, the free encyclopedia)

Pearls – The Birthstone of June – Part 6

From other species

A shell of the Indian volute, Melo melo, surrounded by a number of pearls from this species

Conch pearl pendant

Biologically speaking, under the right set of circumstances, almost any shelled mollusk can produce some kind of pearl. However, most of these molluskan pearls have no luster or iridescence. The great majority of mollusk species produce pearls which are not attractive, and are sometimes not even very durable, such that they usually have no value at all, except perhaps to a scientist or 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 mussels, edible oysters, escargot snails, and so on. The GIA and CIBJO now simply use the term ‘pearl’ (or, where appropriate, the more descriptive term ‘non-nacreous pearl’) when referring to such items and, under Federal Trade Commission rules, various mollusk pearls may be referred to as ‘pearls’, without qualification.

A few species produce pearls that can be of interest as gemstones. These species include the bailer shell Melo, the giant clam Tridacna, various scallop species, Pen shells Pinna, and the Haliotis iris species of abalone. Pearls of abalone, or paua, are mabe pearls, or blister pearls, unique to New Zealand waters and are commonly referred to as ‘blue pearls’. They are admired for their incredible luster and naturally bright vibrant colors that are often compared to opal. 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 or pink conch, Strombus gigas, a large sea snail or marine gastropod from the Caribbean Sea. 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 Triplofusus papillosus.

The second largest pearl known was found in the Philippines in 1934 and is known as the Pearl of Lao Tzu. It is a naturally occurring, non-nacreous, calcareous concretion (pearl) from a giant clam. Because it did not grow in a pearl oyster it is not pearly; instead the surface is glossy like porcelain. Other pearls from giant clams are known to exist, but this is a particularly large one weighing 14 lb (6.4 kg).

The largest known pearl (also from a giant clam) is the Pearl of Puerto, also found in the Philippines by a fisherman from Puerto Princesa, Palawan Island. The enormous pearl is 30 cm wide (1 ft), 67 cm long (2.2 ft) and weighs 75 lb.

More about Pearls in Part 7.

(Information from Wikipedia, the free encyclopedia)

Pearls – The Birthstone of June – Part 5

Types of Cultured Pearls

A blister pearl, a half-sphere, formed flush against the shell of the pearl oyster.

Keshi pearls, although they often occur by chance, are not considered natural. They are a byproduct of the culturing process, and hence do not happen without human intervention. They are quite small, typically only a few millimeters. Keshi pearls are produced by many different types of marine mollusks and freshwater mussels in China. Keshi pearls are actually a mistake in the cultured pearl seeding process. In seeding the cultured pearl, a piece of mantle muscle from a sacrificed oyster is placed with a bead of mother of pearl within the oyster. If the piece of mantle should slip off the bead, a pearl forms of baroque shape about the mantle piece which is entirely nacre. Therefore, a Keshi pearl could be considered superior to cultured pearls with a mother of pearl bead center. In the cultured pearl industry, the resources used to create a mistaken all nacre baroque pearl is a drain on the production of round cultured pearls. Therefore, they are trying to improve culturing technique so that keshi pearls do not occur. All nacre pearls may one day be limited to natural found pearls. Today many “keshi” pearls are actually intentional, with post-harvest shells returned to the water to regenerate a pearl in the existing pearl sac.

Tahitian pearls, frequently referred to as black pearls, are highly valued because of their rarity; the culturing process for them dictates a smaller volume output and they can never be mass-produced because, in common with most sea pearls, the oyster can only be nucleated with one pearl at a time, while freshwater mussels are capable of multiple pearl implants. 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 oysters Pinctada margaritifera found in Tahiti and many other Pacific islands including the Cook Islands and Fiji are being 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 pearls are very rarely black: they are usually shades of green, purple, aubergine, blue, grey, silver or peacock (a mix of several shades, like a peacock’s feather).

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 pearls”.

The correct definition of a South Sea pearl – as described by CIBJO and 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.

South Sea pearls are the largest and rarest of the cultured pearls – making them the most valuable. Prized for their exquisitely beautiful ‘orient’ or lustre, South Sea pearls are now farmed in various parts of the world where the Pinctada maxima oysters can be found, with the finest South Sea pearls being produced by Paspaley along the remote coastline of North-Western Australia. White and silver colored South Sea pearls tend to come from the Broome area of Australia, while golden colored ones are more prevalent in the Philippines and Indonesia.

A farm in the Gulf of California, Mexico, is culturing pearls from the black lipped Pinctada mazatlanica oysters and the rainbow lipped Pteria sterna oysters. Also called Concha Nácar, the pearls from these rainbow lipped oysters fluoresce red under ultraviolet light.

More about Pearls, the birthstone of June, in Part 6 of this series.

(Information from Wikipedia, the free encyclopedia)

Pearls – The Birthstone of June – Part 4

Imitation pearls

Some imitation pearls (also called shell pearls) are simply made of mother-of-pearl, coral or conch 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.

Gemological identification

A well-equipped gem testing laboratory can distinguish natural pearls from cultured pearls by using gemological X-ray equipment to examine the center of a pearl. With X-rays 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 non-beaded 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. Another method of testing for imitations is to rub two pearls against each other. Imitation pearls are completely smooth, but natural and cultured pearls are composed of nacre platelets, making both feel slightly gritty.

Value of a natural pearl

Pearl tiara of Empress Eugénie (1853) featuring 212 natural pearls, Louvre, Paris.

Fine quality natural pearls are very rare jewels. Their values are determined similarly to those of other precious gems, according to size, shape, color, quality of surface, orient and luster.

Single natural pearls are often sold as collectors’ items, 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. (In 1917, jeweler Pierre Cartier purchased the Fifth Avenue mansion that is now the New York Cartier store in exchange for a matched double strand of natural pearls Cartier had been collecting for years; at the time, it was valued at US$1 million.)

The introduction and advance of the cultured pearl hit the pearl industry hard. Pearl dealers publicly disputed the authenticity of these new cultured products, and left many consumers uneasy and confused about their much lower prices. Essentially, the controversy damaged the images of both natural and cultured pearls. By the 1950s, when a significant number of women in developed countries could afford their own cultured pearl necklace, natural pearls were reduced to a small, exclusive niche in the pearl industry.

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. 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.

Read more about Pearls in Part 5 of this series!

(Information from Wikipedia, the free encyclopedia)

Pearls – The Birthstone of June – Part 3

Creation

Diagram comparing a cross-section of a cultured pearl, upper, with a natural pearl, lower

Pearls are formed inside the shell of certain mollusks as a defense mechanism against a potentially threatening irritant such as a parasite inside the shell, or an attack from outside that injures the mantle tissue. The mollusk creates a pearl sac to seal off the irritation. Pearls are thus the result of an immune response analogous in the human body to the capture of an antigen by a phagocyte (phagocytosis).

The mollusk’s mantle (protective membrane) deposits layers of calcium carbonate (CaCO3) in the form of the mineral aragonite or a mixture of aragonite and calcite (polymorphs with the same chemical formula, but different crystal structures) held together by an organic horn-like compound called conchiolin. The combination of aragonite and conchiolin is called nacre, 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 mollusk’s body. These small particles or organisms gain entry when the shell valves are open for feeding or respiration. In cultured pearls, the irritant is typically an introduced piece of the mantle epithelium, with or without a spherical bead (beaded or beadless cultured pearls).

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, irritated by the intruder, forms a pearl sac of external mantle tissue cells and 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.

Typically, the build-up of a natural pearl consists of a brown central zone formed by columnar calcium carbonate (usually calcite, sometimes columnar aragonite) and a yellowish to white outer zone consisting of nacre (tabular aragonite). In a pearl cross-section such as the diagram, these two different materials can be seen. The presence of columnar calcium carbonate rich in organic material indicates juvenile mantle tissue that formed during the early stage of pearl development. Displaced living cells with a well-defined task may continue to perform their function in their new location, often resulting in a cyst. Such displacement may occur via an injury. The fragile rim of the shell is exposed and is prone to damage and injury. Crabs, other predators and parasites such as worm larvae may produce traumatic attacks and cause injuries in which some external mantle tissue cells are disconnected from their layer. Embedded in the conjunctive tissue of the mantle, these cells may survive and form a small pocket in which they continue to secrete calcium carbonate, their natural product. The pocket is called a pearl sac, and grows with time by cell division. The juvenile mantle tissue cells, according to their stage of growth, secrete columnar calcium carbonate from pearl sac’s inner surface. In time, the pearl sac’s external mantle cells proceed to the formation of tabular aragonite. When the transition to nacre secretion occurs, the brown pebble becomes covered with a nacreous coating. During this process, the pearl sac seems to travel into the shell; however, the sac actually stays in its original relative position the mantle tissue while the shell itself grows. After a couple of years, a pearl forms and the shell may be found by a lucky pearl fisher.

Cultured pearls

From Toba Pearl Island, Japan

Cultured pearls are the response of the shell to a tissue implant. A tiny piece of mantle tissue (called a graft) from a donor shell is transplanted into a recipient shell, causing a pearl sac to form into which the tissue precipitates calcium carbonate. There are a number of methods for producing cultured pearls: using freshwater or seawater shells, transplanting the graft into the mantle or into the gonad, and adding a spherical bead as a nucleus. Most saltwater cultured pearls are grown with beads. Trade names of cultured pearls are Akoya, white or golden South sea, and black Tahitian. Most beadless cultured pearls are mantle-grown in freshwater shells in China, and are known as freshwater cultured pearls.

Cultured pearls can be distinguished from natural pearls by X-ray examination. Nucleated cultured pearls are often ‘preformed’ as they tend to follow the shape of the implanted shell bead nucleus. After a bead is inserted into the oyster, it secretes a few layers of nacre around the bead; the resulting cultured pearl can then be harvested in as few as twelve to eighteen months.

When a cultured pearl with a bead nucleus is X-rayed, it reveals a different structure to that of a natural pearl (see diagram). A beaded cultured pearl shows a solid center with no concentric growth rings, whereas a natural pearl shows a series of concentric growth rings. A beadless cultured pearl (whether of freshwater or saltwater origin) may show growth rings, but also a complex central cavity, witness of the first precipitation of the young pearl sac.

More about Pearls in Part 4 of this series.

(Information from Wikipedia, the free encyclopedia)

Pearls – The Birthstone of June – Part 2

Definition

Picture of a black pearl and a shell of the black-lipped pearl oyster. The iridescent colors originate from nacre layers.

All shelled mollusks can, by natural processes, produce some kind of “pearl” when an irritating microscopic object becomes trapped within its mantle folds, but the great majority of these “pearls” are not valued as gemstones. Nacreous pearls, the best-known and most commercially significant, are primarily produced by two groups of molluskan bivalves or clams. A nacreous pearl is made from layers of nacre, by the same living process as is used in the secretion of the mother of pearl which lines the shell.

Natural (or wild) pearls, formed without human intervention, are very rare. Many hundreds of pearl oysters or mussels must be gathered and opened, and thus killed, to find even one wild pearl; for many centuries, this was the only way pearls were obtained, and why pearls fetched such extraordinary prices in the past. Cultured pearls are formed in pearl farms, using human intervention as well as natural processes.

One family of nacreous pearl bivalves – the pearl oyster – lives in the sea, while the other – a very different group of bivalves – lives in freshwater; these are the river mussels such as the freshwater pearl mussel. Saltwater pearls can grow in several species of marine pearl oysters in the family Pteriidae. Freshwater pearls grow within certain (but by no means all) species of freshwater mussels in the order Unionida, the families Unionidae and Margaritiferidae.

Freshwater and Saltwater Pearls

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

Freshwater pearls form in various species of freshwater mussels, family Unionidae, 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 (where they are protected under law). Most freshwater cultured pearls sold today come from China.

Saltwater pearls grow within pearl oysters, family Pteriidae, which live in oceans. Saltwater pearl oysters are usually cultivated in protected lagoons or volcanic atolls.

More about the June Birthstone, Pearl, in Part 3 of this series.

(Information from Wikipedia, the free encyclopedia)

Pearls – The birthstone of June – Part 1

pearl is a hard, glistening object produced within the soft tissue (specifically the mantle) of a living shelled mollusk or another animal, such as a conulariid (oyster). Just like the shell of a mollusk, a pearl is composed of calcium carbonate (mainly aragonite or a mixture of aragonite and calcite) in minute crystalline form, which has been deposited in concentric layers. The ideal pearl is perfectly round and smooth, but many other shapes, known as baroque pearl can occur. The finest quality natural of pearls have been highly valued as gemstones and objects of beauty for many centuries. Because of this, pearl has become a metaphor for something rare, fine, admirable and valuable.

The most valuable pearls occur spontaneously in the wild, but are extremely rare. These wild pearls are referred to as natural pearls. Cultured or farmed pearls from pearl oysters and freshwater mussels make up the majority of those currently sold. Imitation pearls are also widely sold in inexpensive jewelry, but the quality of their iridescence is usually very poor and is easily distinguished from that of genuine pearls. Pearls have been harvested and cultivated primarily for use in jewelry, but in the past were also used to adorn clothing. They have also been crushed and used in cosmetics, medicines and paint formulations.

Whether wild or cultured, gem-quality pearls are almost always nacreous and iridescent, like the interior of the shell that produces them. However, almost all species of shelled mollusks are capable of producing pearls (technically “calcareous concretions”) of lesser shine or less spherical shape. Although these may also be legitimately referred to as “pearls” by gemological labs and also under U.S. Federal Trade Commission rules, and are formed in the same way, most of them have no value except as curiosities.

Image result for Pearls

Physical properties

Structure of nacre layers, wherein aragonite plates are separated by biopolymers, such as chitin, lustrin and silk-like proteins.

The unique luster of pearls depends upon the reflection, refraction, and diffraction of light from the translucent layers. The thinner and more numerous the layers in the pearl, the finer the luster. The iridescence 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. The very best pearls have a metallic mirror-like luster.

Because pearls are made primarily of calcium carbonate, they can be dissolved in vinegar. Calcium carbonate is susceptible to even a weak acid solution because the crystals react with the acetic acid in the vinegar to form calcium acetate and carbon dioxide.

More about the June Birthstone, Pearl, in Part 2 of this series.

(Information from Wikipedia, the free encyclopedia)

MEMORIAL DAY

Memorial Day (or less commonly called Decoration Day) is a federal holiday in the United States for remembering and honoring people who have died while serving in the United States Armed Forces. The holiday is currently observed every year on the last Monday of May. Memorial Day was previously observed on May 30 from 1868 to 1970. In 2019, Memorial Day falls on May 27, 2019.

Memorial Day is considered the unofficial start of the summer vacation season in the United States, while Labor Day marks its end on the first Monday of September.

Many people visit cemeteries and memorials on Memorial Day, particularly to honor those who died in military service. Many volunteers place an American flag on each grave in national cemeteries.

Two other days celebrate those who serve or have served in the U.S. military: Veterans Day, which celebrates the service of all U.S. military veterans; and Armed Forces Day, a minor U.S. remembrance celebrated earlier in May, specifically honoring those currently serving in the U.S. military.

History

The history of Memorial Day in the United States is so controversial that it constitutes an area of research. At Columbus [Georgia] State University there is a Center for Memorial Day Research. It, together with the University of Mississippi’s Center for Civil War Research, are excellent starting points for investigating the topic.

1870 Decoration Day parade in St. Paul, Minnesota

The practice of decorating soldiers’ graves with flowers is an ancient custom. Soldiers’ graves were decorated in the U.S. before and during the American Civil War.

Some believe that an annual cemetery decoration practice began before the American Civil War and thus may reflect the real origin of the “memorial day” idea. Annual Decoration Days for particular cemeteries are still held on a Sunday in late spring or early summer in some rural areas of the American South, notably in the mountain areas. In cases involving a family graveyard where remote ancestors, as well as those who died more recently, are buried, this may take on the character of an extended family reunion to which some people travel hundreds of miles. People gather, put flowers on graves, and renew contacts with relatives and others. There often is a religious service and a picnic-like “dinner on the grounds”, the traditional term for a potluck meal at a church.

21st century

The United States Marine Band on Memorial Day

Memorial Day endures as a holiday which most businesses observe because it marks the unofficial beginning of summer. The Veterans of Foreign Wars (VFW) and Sons of Union Veterans of the Civil War (SUVCW) advocated returning to the original date, although the significance of the date is tenuous.

In 2000, Congress passed the National Moment of Remembrance Act, asking people to stop and remember at 3:00 PM.

On Memorial Day, the flag of the United States is raised briskly to the top of the staff and then solemnly lowered to the half-staff position, where it remains only until noon. It is then raised to full-staff for the remainder of the day.

Across the United States, the central event is attending one of the thousands of parades held on Memorial Day in large and small cities. Most of these feature marching bands and an overall military theme with the Active Duty, Reserve, National Guard and Veteran service members participating along with military vehicles from various wars.

(Information from Wikipedia, the free encyclopedia)

The Mystery of Oak Island – Part 7

Theories

Natural sinkholes

Wide-ranging speculation exists about how the pit was formed and what it might contain. According to Joe Nickell, there is no treasure; the pit is a natural phenomenon, probably a sinkhole connected to limestone passages or caverns. Suggestions that the pit is a natural phenomenon (accumulated debris in a sinkhole or geological fault) date to at least 1911. A number of sinkholes and caves, to which the “booby traps” are attributed, exist on the mainland near the island.

Its resemblance to a human-made pit has been suggested as partly due to the texture of natural, accumulated debris in sinkholes: “This filling would be softer than the surrounding ground, and give the impression that it had been dug up before”. The “platforms” of rotten logs have been attributed to trees, damaged by “blowdowns” (derechos) or wildfires, periodically falling (or washing into) the hollow.

Another pit, similar to the early description of the “money pit”, was discovered in the area in 1949 when workmen were digging a well on the shore of Mahone Bay. At a point where the earth was soft, “At about two feet down a layer of fieldstone was struck. Then logs of spruce and oak were unearthed at irregular intervals, and some of the wood was charred. The immediate suspicion was that another money pit had been found.”

Treasure Trove

According to the earliest theory, the pit held a pirate treasure buried by Captain Kidd; Kidd reportedly conspired with Henry Avery, and Oak Island was their community bank. Another pirate theory involved Edward Teach (Blackbeard), who said that he buried his treasure “where none but Satan and myself can find it.”

An additional proposed explanation is that the pit was dug by Spanish sailors to hold treasure from a wrecked galleon or British troops stationed there during the American Revolution. Others claim that British marines dug the pit to store the loot acquired from the British invasion of Cuba, valued at about £1,000,000 pounds (about $180,000,000 in 2015). John Godwin wrote that given the apparent size and complexity of the pit, it was probably dug by French Army engineers hoping to hide the treasury of the Fortress of Louisbourg after it fell to the British during the Seven Years’ War.

Artifacts

Marie Antoinette’s jewels

Marie Antoinette’s jewels, missing except for specimens in museum collections, have been reportedly hidden on the island. On October 5, 1789, an angry mob of Parisian working women was incited by revolutionaries and marched on the Palace of Versailles. According to the undocumented story, Marie Antoinette instructed her maid (or a lady-in-waiting) to take the jewels and flee. The maid fled to London with the jewels and (perhaps) other treasures, such as artwork or documents, secreted on her person or in her luggage. The woman then fled from London to Nova Scotia. Using royal connections, she contracted with the French Navy to construct the Oak Island pit. In late 2017 the first possible evidence of this theory seemed to have been validated by the discovery of a 500-year-old brooch containing a large garnet.

Bacon-Shakespeare authorship

In his 1953 book, The Oak Island Enigma: A History and Inquiry Into the Origin of the Money Pit, Penn Leary wrote that the pit was used to hide manuscripts indicating that Francis Bacon was the author of William Shakespeare’s works and a leader of the Rosicrucians. Leary’s “The Second Cryptographic Shakespeare”, published in 1990, identified ciphers in Shakespeare’s plays and poems which pointed to Bacon’s authorship. Author and researcher Mark Finnan elaborated on Leary’s Oak Island theory, which was also used in the Norwegian book Organisten (The Seven Steps to Mercy) by Erlend Loe and Petter Amundsen and the TV series Sweet Swan of Avon.

Masonic and other artifacts

In his book, Oak Island Secrets, Mark Finnan noted that many Masonic markings were found on Oak Island, and the shaft (or pit) and its mysterious contents seemed to replicate aspects of a Masonic initiation rite involving a hidden vault with a sacred treasure. Joe Nickell identifies parallels between Oak Island accounts, the “Secret Vault” allegory in York Rite Freemasonry and the Chase Vault on Barbados. Freemason Dennis King examines the Masonic aspects of the Oak Island legend in his article, “The Oak Island Legend: The Masonic Angle”. Steven Sora speculated that the pit could have been dug by exiled Knights Templar and might be the final resting place of the Holy Grail or the Ark of the Covenant.

Another theory holds that the Rosicrucians and their reported leader, Francis Bacon, organized a secret project to make Oak Island the home of its legendary vault with ingenious means to conceal ancient manuscripts and artifacts. Researchers and cryptographers such as Petter Amundsen and Daniel Ronnstam claim to have found codes hidden in Shakespeare, rock formations on the island, and clues hidden in other 16th- and 17th-century art and historical documents. According to Daniel Ronnstam, the stone found at 90 feet (27 m) contains a dual cipher created by Bacon.

Other theories

Author Joy Steele suggests that the money pit is actually a tar kiln dating to the historical period when “Oak Island served as a tar-making location as part of the British naval stores industry”.  When marine biologist Barry Fell attempted to have the symbols on the stone translated during the late 1970s, he said that the symbols resembled the Coptic alphabet and read: “To escape contagion of plague and winter hardships, he is to pray for an end or mitigation the Arif: The people will perish in misery if they forget the Lord, alas.” According to Fell’s theory, Coptic migrants sailed from North Africa to Oak Island and constructed the pit. However, Fell is not considered to be credible by most mainstream academics.

Is the lost treasure of Oak Island real or not?

(Information from Wikipedia.com)