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Pearls

Thursday, 12 March 2009 23:02 by Admin
     
 
Pearls From Burma (Myanmar)

Many people only associate Japan, China, and Tahiti with pearl culturing.
There are in fact many other countries also culturing
pearls, of which Burma (Myanmar) is one. Presently,
all pearl farming in Burma (Myanmar) occurs in the
Mergui archipelago which consists of more than
800 individual islands. Mergui, which is the
Mergui archipelago's main sea port is believed to
be home to around 70,000 people, all of whom
believe the pearl to be a symbol of grace,
glory and pride. Mergui was for centuries
a thriving port that has been Siamese (Thai),
Burmese (Myanmar), and more latterly
British ruled, which is how it remained
until
Burma (Myanmar) won independence in 1948.

Pearling for natural pearls is said to have been
undertaken in Myanmar by British colonists as far
back as the 1890's, and by around 1910 it is said that
over 100 ships from almost 70 countries were in Myanmar diving for pearls, with much of the diving labor being provided by the local Moken people (sea gypsies), who are quite possibly the oldest inhabitants in the entire region. At this time pearl divers collected pearls via free diving, and all Mergui pearls were recovered from wild oysters.

 
 
  the Japanese arrived, founded a joint-venture with a local Myanmar company and introduced pearl culturing / farming,
although until around 2000 wild oysters were also being fished / collected. From almost the moment that the first pearls were harvested in 1957 they were considered the world's finest, and were highly sought-after, just as they still are today. The other major development in 1957 was the introduction of diving suits which allowed pearl divers to go deeper, and for longer than had previously been possible using free diving methods. Additionally, the introduction of diving suits saw a dramatic rise in the number of months each year that pearls could be harvested, from just three months of every year, to nine months of every year. The main farm site for the aforementioned Japanese-Burmese joint-venture was, and still is, on Sir Malcolm J Island, and is said to be the oldest South Sea pearl farm in the world still in operation today, albeit minus the original Japanese pearl technicians who were unceremoniously deported after the Myanmar pearl industry was nationalized in 1963.
 
 
 
 
 
each year that pearls could be harvested, from just three months of every year, to nine months of every year. The main farm site for the aforementioned Japanese-Burmese joint-venture was, and still is, on Sir Malcolm J Island, and is said to be the oldest South Sea pearl farm in the world still in operation today, albeit minus the original Japanese pearl technicians who were unceremoniously deported after the Myanmar pearl industry was nationalized in 1963.

The process of Pearl farming / culturing is necessary because while pearls do occur naturally they do so extremely rarely (perhaps one in every ten thousand pearls), and a low naturally available south sea pearl supply coupled with ever-increasing demand dictated that pearl culturing was necessary.

 
 
    The pearl culturing process comprises five key steps :

1. Beeding – This is where pearl farmers select the very best pearls, those expected to produce a good pearl harvest.

2. Nucleating – This is the delicate process of introducing an irritant (most frequently referred to as a nucleus), into the oyster. This process triggers the oyster into producing nacre, the substance from which pearls are made.

3. Feeding / Growing – Oysters are kept in sheltered bays in the sea in optimum growing conditions and moved deeper / shallower each and every day, depending upon their needs.

4. Oyster Care – Pearls are periodically removed from the sea for cleaning, health checks and treatments so as to ensure they live – Pearls have a very high mortality rate with perhaps as little of half of all pearls farmed surviving any given year.

5. Harvesting – Pearls are opened and checked for gem quality pearls, which make up as little as 5% of any pearl harvest. Often at this stage, if still alive, the oyster will be nucleated with a new, often larger nucleus so the process starts over.
 
 
 
 
 
 
 

Burmese pearl culturing (which concentrates solely on saltwater pearls), uses the two varieties of the Pinctada Maxima oyster, Silver Lipped, and Gold Lipped. The Pinctada Maxima oyster is the largest of all pearl producing oysters and can weigh up to 5 kg, and have a diameter of up to 35 cm. The Pinctada Maxima oyster produces what are commonly referred to as South Sea pearls. South Sea pearls are the rarest, largest, and most valuable of all cultured pearl types.

When purchasing your Myanmar South Sea pearls, pay particular attention to the five key quality factors:


1. Luster – This is the term used to describe the beautiful, intense, deep shine exhibited by pearls which is caused by a combination of the light reflecting off the surface of the pearl, and light refracting off the internal layers of nacre, sometimes referred to as Mother-Of-Pearl.

 

2. Surface – The surface quality of pearls can vary widely and markings / blemishes have a substantial impact upon a pearl's overall value.

 

3. Shape – As a general rule of thumb, the more round a pearl is, the more valuable it is. However, it is also important to consider that certain shapes, when set correctly, can appear round.

 

4. Color – Pearls from Myanmar can be silver-white to deep gold, and other colors too, including champagne, cream, pink, blue, green and yellow, but are most commonly golden. The golden South Sea pearl is considered to be the most beautiful, and is therefore the most valuable.

 

5. Size – The most commonly found size of Myanmar South Sea Pearls is 12 mm – 13 mm, with dramatic price increases occurring for pearls over 16 mm in diameter.

 

We do hope you found our blog post interesting, and would be very interested to hear your feedback / comments on the same.

 

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Rubies

Thursday, 12 March 2009 20:36 by Admin
     
 
Rubies From Vietnam

While Vietnam is a country with many different types of gemstone
deposits, today we will examine rubies.


With the Vietnamese economy in the process of changing
from a communist to a capitalist economy, you might think
that the gemstone business is still entirely state-run, but
there are in fact only two major state-run / controlled
entities in the gemstone arena in Vietnam, The Vietnam
National Gem & Gold Corporation, which concentrates on
sales of controlled gemstones and minerals, and The
Vietnam National Gold, Silver & Gemstones Corporation,
specializing in the jewelry and gold markets. The fact is
that even now, most gemstone and gemstone-related
business in Vietnam is conducted primarily by private
companies.

Depending upon the location they were mined at, gemstones generally have specific characteristics that help to confirm that any given stone was mined at the location claimed. Rubies from Vietnam do not usually display the deep, rich coloration and high levels of clarity associated with say Burma (Myanmar), or Sri Lanka (Ceylon) mined rubies, and tend to exhibit purple hues, so are therefore sold at more competitive prices than the traditional deep red coloration. This oftentimes allows the informed buyer to purchase beautiful gemstones at significant reductions as heat-treated Vietnamese rubies are very similar in coloration to rubies from Burma (Myanmar).

 
 
 

In the north of Vietnam rubies are mined at Luc Yen district in Yen Bai, a large town / small city situated to the north west of Hanoi, where high quality deposits were discovered in the late 1980's. This discovery paved the way for large scale mining operations and explorations which shortly thereafter led to further significant ruby deposit discoveries in central Vietnam at Nghe An, the birthplace of Ho Chi Minh, and very heavily targeted by the US during the War. The most recent ruby deposits in Vietnam were discovered in southern Vietnam at Quy Chau, around 1990 and turned the area from one of the poorest in Vietnam to a boomtown very quickly.

Entrepreneurs from neighboring Thailand soon arrived and started exporting Vietnamese rubies back to Bangkok where they were heat treated to improve the stone's color and clarity characteristics.

Ruby is made up of corundum, with chromium
impurities being responsible for the beautiful
red coloration. Ruby is the most valuable gem
in the corundum family and has long been
considered “the King of gemstones”. With a
Moh's Scale of Hardness rating of 9, Ruby is
second only to diamond in this regard, and is
hard-wearing, durable and versatile, making it
perfectly suited to all jewelry purposes.

 
 
 

As with diamonds and other gemstones the value of rubies is dependent upon the 4C's – Cut, Color, Clarity and Carat, with a particular emphasis placed on color, and clarity / transparency, and even with good quality deposits it is extremely hard and a very expensive exercise trying to source natural rubies that have not been treated. The most common treatment for rubies is heat treating which enhances and intensifies color, and removes “silk” which is the term used to describe small inclusions that occur in almost all rubies thereby improving clarity. Heat treatment of rubies is accepted as the norm and is considered permanent. When purchasing a ruby assume that the stone has been heat treated unless specifically stated otherwise.

Subscribe to our blog feed or check back soon for more interesting facts about gemstones.

 
 

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Kunzite – The Gemstone For All Seasons

Wednesday, 11 March 2009 15:09 by Admin
     
 
Kunzite – The Gemstone For All Seasons

Kunzite is a member of the Spodumene family of minerals, and while Spodumene
has been known of for a very long time, commercial quantity,
gem quality Kunzite was not discovered until as
recently as 1902.


Kunzite is most commonly known and referenced
as a pink
/ lilac-pink stone but is actually also
sometimes found as colorless stone. A Moh's
Scale Of Hardness rating of around 7 and
relative fragility makes Kunzite gemstones
best suited to pendant, earrings, and brooch
applications.


Although gem quality Kunzite was originally discovered in
the US, today the most notable deposits are mined in Brazil, at Minas Gerais, Paraiba, Urupuca, and Rio Grande do Norrte, and in Afghanistan, where the most important Kunzite mines are Suraj and Mawi, although significant other mines operate in Nilaw and Korgal. All of the aforementioned areas have beenactively mined since the 1970's and continue to be so despite the difficulties involved with accessing the area. It is the Nuristan regionin Afghanistan that produces what are considered to be the most beautiful Kunzite stones available today – they exhibit wonderful deep pink and violet shades.

 
 
  Unsurprisingly, and owing somewhat to their geographical closeness to each other, many of the Kunzite stones mined in Afghanistan find their way over the border into Pakistan where the gems are then cut, polished anddistributed. A large proportion of the Pakistani gem cutters were originally trained in Sri Lanka (Ceylon), an island off the coast of India and enjoys a long and steemed history in the gemstone industry. Training is particularly important when cutting Kunzite becauseof its perfect cleavage and strong pleochroism. In order for the pleochroism and deepest coloration to be displayed a Kunzite stone must be cut perfectly.
 
 
 
As mentioned above, and like only a few other gemstones, Kunzite displays pleochroism. This is an optical phenomenon which explained simply means that a Kunzite gemstone viewed from different angles will appear to be different colors. Kunzite is trichroic, and the three colors than can be viewed from differing angles are usually pink, clear and violet.
 
 
 
     
 

Kunzite is traditionally valued for its beautiful colorations, so when selecting your Kunzite gemstone first examine the color, because the more intense the coloration is, the more valuable your stone will be. Clarity and brilliance also have a significant effect upon value so also consider these points carefully.

Common treatments for Kunzite include heat treatment and irradiation, both of which are used to intensify and deepen the stones coloration. While heat treatment is considered to be a permanent color enhancement, stones that have been irradiated only can suffer from loss of richness of coloration over time. Be aware that prolonged exposure to bright light / the sun can cause a Kunzite stone to lose its coloration. For this reason Kunzite has frequently been referred to as the evening stone.

 
     

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