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Cultured Pearls
Cultured Pearls are those in which humans take a helping
hand. By actually inserting a foreign object into the
tissue of an oyster or mollusk, Pearl farmers can induce
the creation of a Pearl. The same natural process of
Pearl creation takes place. Like natural Pearls,
cultured Pearls grow inside a living organism. However,
they do not begin as accidental intruders to the shell.
Instead, humans insert mother-of-Pearl beads or other
shapes into a mollusk. Over time they become coated with
nacre. The depth of the nacre coating depends on how
long the beads are left in place before being harvested.
A Meticulous Culturing Process:
Millions of oysters are nucleated every year, but only a
small proportion live to produce fine quality cultured Pearls. Many
oysters don&9;t survive the nucleating process; others are weak and fall
prey to disease. Heavy rains may flood the bays with fresh water,
reducing their salinity, and killing the oysters. Sometimes, certain
species of phytoplankton undergo explosive growth, creating the dreaded
"red tide," which exhausts the oxygen in the water, and suffocates the
oysters. Then there are typhoons, the attacks of predators and
parasites, lack of sufficient nutrients in the water.
The Art of Cultured Pearls:
Cultured Pearls share the same properties as natural
Pearls. Oysters form cultured Pearls in an almost
identical fashion. The only difference is a person
carefully implants the irritant in the oyster, rather
than leaving it to chance. We then step aside and let
nature create its miracle. How Pearls are cultivated and
harvested Early on, Pearl cultivation depended entirely
on wild oysters. Later you'll learn that, in some cases,
the same applies today. But modern Pearl cultivation has
become more selective.
This Amazing Culturing Process Discovery
This discovery revolutionized the Pearl industry, because
it allowed Pearl farmers to reliably cultivate large
numbers of high-quality Pearls. In contrast to natural
Pearls—which have widely varying shapes, sizes, and
qualities, and which are difficult to find—cultured
Pearls could be "designed" from the start to be round
and primarily flawless. The oysters could be monitored
for up to two years until each Pearl is fully formed,
thus better ensuring their health and survival. And the
Pearls could be grown by the tens of thousands, thereby
bringing their cost down to a point where Pearls became
accessible to large numbers of people around the world.
Painstaking and Patient Efforts:
On average, only 50 percent of nucleated oysters survive
to bear Pearls, and of them, only 20 percent bear Pearls that are
marketable. The rest are simply too imperfect, too flawed to be called
jewels. And so, a perfect Pearl is truly a rare event, blessed by
Nature. Less than 5 percent of nucleated oysters yield Pearls of such
perfect shape, luster and color as to be considered fine gem quality.
Japanese Domination in Cultured Pearls
Nearly all of the world&9;s supply of cultured saltwater
Pearls is produced by the Japanese, who have perfected the techniques of
saltwater Pearl cultivation. These Pearls are commonly produced by
placing a small mother-of-Pearl bead enclosed in a piece of mantle
tissue in the body of the oyster. The oysters are then placed in cages
that are suspended into sheltered bays for the period of time (up to 4
years) required for Pearl formation.
China's Cultured Pearl Revolution
Now China is
in what I call its Third Pearl Wave. Starting in the 1990s, China
surprised the market with products that are revolutionizing Pearling.
The shapes, luster, and colors of the new Chinese production often match
original Biwa quality and sometime even surpass it; certainly the new
orange and peach-colored Pearls are unique. As testimony to China&9;s
achievement, their freshwater Pearls are round enough and good enough to
pass as Japanese akoya. China already sells round white Pearls up to 7mm
for perhaps a tenth the price of Japanese cultured saltwater Pearls.
Except for
the old Arabic practice of sun-bleaching in the Persian Gulf, naturals
were practically never processed. Bleaching, dying, and polishing do
occur. Chinese Pearls that are nearly white or mottled are usually
bleached to make them whiter and more uniform. With the same methods
perfected by the Japanese, the Chinese use a mild bleach, bright
fluorescent lights, and heat. They polish surfaces by tumbling Pearls in
pumice or similar substances. The idea, as always, is to facilitate
matching Pearls for strands. Many Chinese Pearls used to be dyed in the
1980s to bright red, blue, lavender, yellow or even black. In response
to contemporary preferences, they now offer a selection of subtle
natural colors. Nucleating an oyster.
Saltwater
Culturing Techniques
The Chinese
have also begun to nucleate some of their freshwater mussels with shell
nuclei implants in both the creatures&9; bodies as well as in their
mantles. Such practices, once perceived as "saltwater culturing
techniques," are a new cultural revolution. How will buyers react who
had been told that cultured freshwater Pearls were all-nacre products?
Will they buy Chinese Pearls if the roundest examples are nacre-coated
shell beads instead? How will such new products be positioned in the
market? Will anyone, including gem testing labs, be able to tell the
difference between tissue-nucleated and bead-nucleated freshwater
Pearls?
Those are
serious new considerations. Even more disquieting is the second
innovation. The Chinese are nucleating mussels with their own
tissue-cultured freshwater Pearls, which result in all-nacre round or
almost round Pearls. Aiming for an even higher percentage of rounds, the
Chinese are even reshaping reject freshwater Pearls into spheres, then
nucleating mussels with them.
Freshwater vs. Saltwater Pearls
A common question posed by many Pearl buyers today is
whether or not a particular strand of Pearls is composed of freshwater
or cultured Pearls. This question cannot have a definitive answer
because freshwater Pearls are in fact cultured Pearls. The reason so
many buyers distinguish cultured a Pearl from freshwater Pearls is
because 'cultured Pearls' is a trade term still used today by many to
describe Akoya Pearls. This is important to understand when shopping for
Pearls because a seller of freshwater Pearls can describe their product
as cultured Pearls. It is always important to identify the origin of the
cultured Pearls to make an informed purchase decision because a strand
of freshwater Pearls will never be as valuable as a strand of equivalent
quality Akoya Pearls.
How to Tell the Difference between Freshwater and
Saltwater Pearls?
Here are some tips on how
to tell the difference between saltwater Pearls and
freshwater Pearls:
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Round saltwater Pearls are perfect
round, while 'round'; freshwater Pearls are not really perfect
round. They are more like potato shaped.
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Saltwater Pearls have better luster
than freshwater Pearls. The luster of freshwater Pearls looks a
little bit dull. Saltwater Pearls look more transparent than
freshwater Pearls (what we refer as lustrous)
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The surface of saltwater Pearls is
smoother than freshwater Pearls.
South Sea Pearls
South Sea Pearls is a generic name for the
Pearls, usually 9mm-16mm in size, produced by the two groups of large
Pearl producing oysters. These oysters can grow to 25-30 cm in size, and
are much rarer than their Akoya counterparts....
Read more...
Tahiti Cultured Pearls
Tahiti cultured Pearls are Pearl concretions
that are secreted inside the black-lipped Pinctada Margaritifera species
of Pearl oysters cultivated mainly in the lagoons of French Polynesia.
They consist of thick Pearly layers containing organic substances..
Read more...
Akoya Pearls
Akoya Pearls are found only in Japan, China,
and Vietnam. Japanese Akoya Pearl farms are shifting towards the warmer
Chinese waters, where these Pearls take only half as long to grow.
Overtone colors of Akoya Pearls include white, cream, rose, silver, and
green...
Read more...
Mabe Pearls
Mabe Pearls are large, hemispherical cultured
Pearls that grow attached to the inside shells of oysters. Mabe Pearls
are of hemispherical shape, grown against the inside of the oyster's
shell, rather than within its tissue. Mabes occasionally appear in
nature...
Read more...
Blister Pearls
A blister Pearl (also called a button Pearl)
is a Pearl that developed attached to the inside of a mollusk's shell.
This type of Pearl must be cut off the shell, and is therefore
hemispherical. Because of their shape, blister Pearls are mostly used
for earrings...
Read more...
Rainbow Mabe Pearls
In general, you would think that all Pearls are round
shaped or spherical. However, Mabe Pearls are not
completely round. They come in various shapes. The
subtle hues give it a unique presence, a quality that
can't be found in other Pearls. Mabe Pearls are suitable
for...
Read more...
Mother of Pearl
Mother of Pearl, also called nacre, is an
iridescent layer of material which forms the shell lining of many
mollusks. The Pearly internal layer of certain mollusk shells, used to
make decorative objects. Also called nacre. Pearl oysters and abalone
are both sources of mother of...
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Keshi Pearls
Tiny Pearls, some a little bigger than a grain
of sand, which form naturally in many cultured Pearl oysters. Keshi is a
Japanese word for "poppy seed". Thus, keshi is also called the seed
Pearl deriving the name from its size. Keshi Pearls are irregularly
shaped...
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The Pearl Myths
There are many myths
about Pearls that have continued through the centuries.
"Pearls of Wisdom", is a common saying and even
shares the title of some books in areas such as
medicine, country living, inspiration and wisdom
collections and Oriental teachings...
Read more...
Back to 'All About Pearls' Summary
Ever since the ancient Egyptians first started creating
jewelry, Pearls have become one of the highest regarded gemstones. Even
today Pearls still hold their value due to the rarity of "mother nature"
creating this form of jewelry. Pearls are created from a core. The core
of a natural Pearl is simply a fragment of shell or fishbone, or a grain
of sand that strays into the unsuspecting Pearl oyster's shell. To
protect itself from this irritant the oyster secretes multiple layers of
nacre, forming a Pearl...
Read more...
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About Cultured Pearls
