gems – An Indian Bureaucrat's Diary http://binoygupta.com Share the life time experiences of a retired Indian Bureaucrat relating to travel and nature Tue, 11 Mar 2008 16:39:47 +0000 en-US hourly 1 https://wordpress.org/?v=6.6.1 Travel India Pearls – the Queen of Gems http://binoygupta.com/travel_india/pearls-queen-gems-cultured-pearls-baroda-pearls-pearl-allah-kokichi-mikimoto-28/ http://binoygupta.com/travel_india/pearls-queen-gems-cultured-pearls-baroda-pearls-pearl-allah-kokichi-mikimoto-28/#comments Thu, 14 Feb 2008 12:27:09 +0000 http://binoygupta.com/?p=28 Read more ›]]>

This article was inspired by two events.
I visited a Hyderabad Pearl exhibition in Calcutta.
I was surprised because there are no pearls in or around Hyderabad.

The fact is that the pearl smiths in Hyderabad import fresh water cultured pearls from China and transform them into beautiful ornaments.

On another occasion, I visited the Central Marine Research Centre in Tuticorin when they had just successfully made cultured pearls.
I saw the entire process.

I even learnt scuba diving there and went down inside the sea where the pearl oysters lived, bred and made the natural pearls.
Pearls are interesting ……..

What is the value of a pearl necklace?
A good pearl necklace is priceless.
A pearl can not be cut, polished and crafted like other gems.

A natural round pearl is a piece of art created by mother nature herself.
A really beautiful pearl is rare.
A necklace made of a number of pearls matching in colour, size, shape and lustre is therefore extremely expensive and worth a furtune.

Baroda Pearls – the most expensive pearl necklace

The Maharajah of Baroda, Khande Rao Gaekwar (rule 1856 – 1870), was one of the greatest jewellery collectors of the 19th century.
Amongst his pearl collections were an ornamental belt of one hundred rows of pearls;a majestic seed pearl and a seven-strand necklace made of natural pearls from the Gulf.

When his descendant Maharajah Pratapsingh Gaekwar (rule 1939 – 1947) married his second wife, Maharani Sita Devi – one of the most flamboyant Maharanis of all time and referred to as the Indian Wallace Simpson – in 1943, Sita Devi received the pearl necklace and other items of jewellery from the Maharajah.
The pearl necklace was last seen on her neck in 1948.
Many items of her jewellery have since been sold in Monaco.
But the necklace remained in Baroda.

The Baroda Pearls – made out of the best pearls in the original necklace – a two-row seven-strand pearl necklace, comprising of impeccably matched 68 of the finest and largest pearls in the world, with a cushion cut Cartier diamond clasp, was auctioned at Christie’s in New York on April 25, 2007 for $7.1 million, setting a new world record for a pearl necklace.


The pearls measure 9.47 to 16.04 mm, from the fourth, fifth, sixth, and seventh strands.
The necklace has a matching pair of natural pearl and diamond ear pendants, a brooch, and a ring.
The previous record was set by a two-strand natural pearl necklace sold for $ 3.1 million at Christie’s in Geneva in November 2004.

Pearl of Allah

The Pearl of Allah (Pearl of Lao-Tse), the largest pearl on record, was recovered by a Muslim diver from a giant clam off the coast of Palawan Island, Philippines on May 7, 1934.
The chief of Palawan took the pearl because it had been found near his island.

Around 1939, Wilburn Dowell Cobb saved the life of the chief’s son.
The chief gifted the pearl to Cobb.
In 1980, Cobb’s heirs sold the pearl to Peter Hofman, a jeweler from Beverly Hills, for $200,000.

Peter Hofman still owns 33 percent interest in the pearl.
The pearl is 9.4 inches long and weighs about 14 lbs.
Its surface bears the semblance of a turbaned face.
The Pearl of Allah is valued at $40 million.
The giant pearl is also called the Pearl of Lao Tsu, after the legendary sixth-century B.C. philosopher known as the father of Taoism.
Replicas of the Pearl of Allah are on display in various museums around the world.

Paradoxically, although referred to as a pearl, and even treated as the largest pearl in the world, the Pearl of Allah is actually a non-nacreous calcareous concretion; and therefore gemmologically speaking, not actually a pearl.

The Hope Pearl

The Hope Pearl is the largest natural salt water pearl ever discovered.
It is a white, drop-shaped blister pearl, measuring approximately 2 x 4 inches, and varying in color from greenish gold on one end to white on the other.
It weighs 1,800 grains (450 carats), or approximately 4 ounces.

It was once owned by Henry Philip Hope, the one-time owner of the Hope Diamond.
Currently, it is displayed in the British Museum of Natural History.

Is the pearl a gem?

A pearl is a hard, round, shiny, lustrous object produced by certain species of the bivalve mollusks – an aquatic animal.

The freshwater pearls are produced by mussels and salt water pearls by oysters.
On the other hand, a gemstone, gem, precious or semi-precious stone is an attractive and valuable piece of mineral.
Pearls are certainly not gems, yet they are included in almost every book and writing on gems for the simple reason that they are used in jewellery.
When we talk of gems, we talk of diamonds, rubies, saphires, emeralds and other precious and semi precious stones………. but we also talk of pearls.
Pearls are prized like gems and widely used in jewellery.
Pearls are also crushed and used in indigenous medicinal formulations, in cosmetics and paint formulations.

Fresh water and salt water pearls

There are two kinds of pearls – fresh water and salt water – depending on where they are formed.

The fresh water pearls are formed in fresh water mussels that live in lakes, rivers, ponds and other bodies of fresh water.
The pearls the Chinese first used – over 4000 years ago – were obviously fresh water pearls because they have been described as not quite round. Even today’s fresh water pearls are not that round.
China with a a total production of 1500 tons in 2006 is the undisputed world leader in fresh water pearl production.

The salt water pearls grow in oysters that live in the oceans, usually in protected lagoons.Over 99% of the salt water pearls we see today are cultured pearls.
Generally, only a single pearl is found in a salt water oyster.
While, a large number of pearls can be found in one fresh water mussel.Natural and cultured pearls

A pearl is formed when a small irritant or parasite penetrates and lodges in the mantle tissue of a mollusk.
The mollusk secretes nacre around this nucleus.
Nacre is a complex combination of crystalline and organic substances which builds up in layers surrounding the irritant forming a pearl.

Natural pearls are formed by chance.
The shape of the pearl depends on the shape of the nucleus.
The shape of a natural pearl is therefore unpredictable.
The odds of formation of a perfect natural pearl are 1 in a million.

Cultured pearls have been given a helping hand.
A foreign object is introduced into a mollusk thereby inducing the mollusc to secrete nacre around it and create a pearl.
The shape of the resultant pearl can be controlled to a great extent.
It is possible to grow large quantities of almost identical cultured pearls.

Today, nearly all pearls in the market – both fresh water and salt water – are cultured.

How to differentiate cultured pearls from natural

The simplest and scientific way of distinguishing cultured pearls from natural pearls is through x-ray.
The x-ray will reveal the nucleus of the pearl.

If the pearl is cultured, you will see the tell tale image of the synthetic nucleus implanted as an irritant.
There will be no visible nucleus in the case of a natural pearl.

The culturing process

Kokichi Mikimoto almost single handedly developed and commercialised the modern cultured pearl industry.
Mikimoto was born in 1858 in Toba City, Japan.
He was the eldest son in a family which ran a noodle restaurant.
He started raising oysters in 1888.
By the late 1890s, he patented a process for culturing mabes (hemispherical pearls).

Over the next two decades, Mikimoto continued with his research in culturing pearls, culminating in 1916 with his patenting a process for culturing spherical pearl.
He developed the modern techniques for culturing pearls and simultaneously pursuaded and convinced the public to accept the cultured pearls.
Mikimoto created the cultured pearl industry that exists today.
Mikimoto died in 1954 at the age of 96.

Technique for culturing pearls

Freshwater pearls and salt water pearls are nucleated differently.

Freshwater cultured pearls are not bead-nucleated.
A small incision is made in the fleshy mantle tissue of a 6 to 12 month old mussel.
A 3 mm square piece of mantle tissue from a donor mussel is inserted inside it.
A single mussel can with stand upto 25 such incisions.
But in practice, only 12-16 incisions are made for production of 24-32 pearls.
The mollusks are then returned to their freshwater environment where they are looked after for 2 to 6 years.
The resulting pearls are of solid nacre, but without a bead nucleus.
These pearls are rarely perfect round.

The salt water pearls are bead-nucleated.
The oysters are opened.
A small incision is made in the gonad (reproductive organ) and a round core or nucleus which is generally a polished bead made from a freshwater mussel shell is surgically implanted into the incision.
The oysters are returned to salt water.
The pearls which will form in about 2 years will be round.
An x-ray will reveal the tell tale nucleus.

Main types of salt water pearls

Today, the cultured pearl industry has effectively and totally replaced the natural pearl industry with production of cultured freshwater; and the three main types of salt water pearls – South Sea, Tahitian, and Mikimoto’s original Akoya pearls.

Pearl culture in India

Natural pearls were once found in plenty in Jam Nagar (Gulf of Kutch) and Thoothukudi (Gulf of Mannar).
Over the years, both these resources were depleted.

And today, India imports almost all her requirement of pearls.
In 1972, the Central Marine Fisheries Research Institute (CMFRI) started an experimental project of pearl culture at Thoothukudi.
The next year CMFRI achieved a breakthrough and produced the first spherical cultured pearl on July 25, 1973.
The Tamil Nadu Fisheries Development Corporation Ltd and Southern Petro Chemical Industries Corporation Ltd. started a joint venture pearl culture project in 1983.
But there has been no commercial success and the project has been leased out to private party.
In 1976, the CMFRI started a pearl oyster hatchery and spats (baby oysters) produced from the hatchery are supplied to pearl producers.

Artificial or synthetic pearls

These are cheap imitations made of glass, plastic, acrylic, etc.

Caring for your Pearls

Pearls have an organic origin. They are scientifically different from gemstones and precious metals.
· They are softer and far more delicate. They can be more easily scratched, cracked, and damaged.
· Chemicals in perfumes and hair spray can harm pearls.
· Even natural body oils and perspiration can dull the pearls’ luster or cloud their brilliance.
· Acids present in lemon juice, citric fruits, etc. corrode pearls.
· For these reasons, your pearls require special care.
· Apply perfume, hair spray, and other cosmetics before putting on the pearls on your person. This way, you will minimise the contact of these products with the pearls.
· After wearing your pearls, wipe them with a soft damp cloth to remove any traces of cosmetic products and body oils.
· Wash the pearls periodically with mild soap water and a soft cloth, to remove any accumulated build-up.
· Store pearls separately, in soft cloth or in a soft-lined container, pouch, or jewellery box away from hard jewellery items, to prevent scratches or other damage. If possible, store them wrapped.
· If the pearls are strung, have the pearls restrung periodically – perhaps once a year or so, if you wear them often – to prevent strand breakage. Knotting the strands between each pearl will prevent all the pearls from falling off, if the strand breaks. Knotting will also prevent the pearls from rubbing against one another and causing damage by friction.
· With a little bit of care, your Queen of Gems will remain bright and lustrous for years to come.

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Ruby http://binoygupta.com/nature/ruby-26/ http://binoygupta.com/nature/ruby-26/#comments Tue, 12 Feb 2008 12:25:40 +0000 http://binoygupta.com/?p=26 Read more ›]]>

The Gemstone of Love and Passion

I am sure you would like to know more about the gem stones.
This article is one of a series of 5 articles covering the four precious gemstones – Diamond, Ruby, Sapphire, Emerald and Pearls (which is really not a gem).

Which colour would you associate with love and passion?
The answer is pretty obvious. Red……… Deep Red.

Deep Red is the colour of love.

It radiates warmth and a strong sense of vitality.
Blood is Deep Red.

The heart is also a Deep Red.

Deep Red is the traditional colour of the rose.

(God alone knows why scientists are still struggling to produce a true black or blue rose).

Red is also the colour of Ruby, the Prince of Gemstones.
Where love is involved, ruby is the undisputed ruler of the fascinating world of gemstones.
Ruby is a form of Corundum
Chemically, Ruby is corundum, a crystalline form of aluminium oxide, found in nature as a mineral.

In this photograph on the right, you can see a piece of natural corundum.

Corundum is the second hardest mineral on Earth (the hardest is diamond).

On the Mohs scale (which is a measure of hardness), the score of corundum is 9.
It is so hard that combined with other additives, it is used as an abrasive – from the common sand paper to large machines for machining metals to the hardest stones.
Pure corundum is colourless.

Traces of other elements like chrome, iron, titanium or vanadium give it colour.


What is a Ruby

Only red corundum can be called ruby.

Corundum of all other colours are classified as sapphires.

This is the photo of a large crystal of uncut ruby.

Its length is about 0.8 inches (2 cm).

On the left is the world largest uncut ruby crystal.

Nicknamed the 125West, this natural ruby crystal weighs 8.2 lbs. or 18,696 carats.

After cutting, it could become the largest ruby in the world.
Earlier, there was some confusion and misclassification.

Red garnets or spinels were also thought to be rubies.
This is the reason why two of the British Crown Jewels, the ‘Black Ruby’ and the ‘Timur Ruby’, were wrongly named rubies, when really they are not rubies, but spinels.
Ruby and India
India was the ruby’s classical country of origin.

For a long time, India was a major supplier of Ruby.

The term ‘corundum’ is derived from the Sanskrit word ‘kuruvinda’.

The Sanskrit word for ruby is ‘ratna raj’, which means ‘king of gemstones’.
Indian rulers gave great importance to rubies.

The insignia of many royal households all over the world are still embedded with rubies.
Where do the finest rubies come from
Today, the finest rubies come from the ruby deposits in Myanmar (Burma).

They are a rich, full red with a slightly bluish hue ‘pigeon-blood-red’.

The finest rubies are termed Myanmar rubies even if they come from some other country, but the term ‘Burmese colour’ would be more appropriate description for them.
There are Ruby deposits in neighbouring Vietnam, near the Chinese border.

Vietnamese Rubies are slightly purplish.

Rubies from Thailand are a darker red towards brown.

The ‘Siamese colour’ is considered only second to the Myanmar rubies.
Improvements
Even natural rubies are improved.
Such improvements include:
· Color alteration,
· Improving transparency by dissolving rutile inclusions, and
· Healing, or even completely filling in, fractures (cracks).

Rubies can be carved.

On the right is a fine piece of carved ruby known as Greenland Carved Ruby.
Synthetic corundum
Surprisingly, beautiful rubies can be made artificially.

In 1837, Gaudin made the first synthetic rubies by fusing alumina at a high temperature with a little chromium as a pigment.

In 1847, Edelman made white sapphire by fusing alumina in boric acid.

In 1877, Frenic and Freil made crystal corundum from which small stones could be cut.

In 1903, Verneuil produced high quality synthetic rubies on a commercial scale by using a flame fusion process.

This simple and inexpensive process is now used to produce flawless single crystal sapphires, rubies and other corundum gems of much larger size than are normally found in nature.
Qualities of a good Ruby

A good ruby more than 3 carats is exceedingly rare and more expensive than an equivalent diamond.

What determines the price of a ruby


· First, its colour. Colour is a ruby’s most important feature.
· Second, inclusions within the ruby. A ruby without any inclusions is extremely rare.
· Third, cut. It is the cut which bring out a gem’s beauty. Only a perfect cut can do justice to a priceless gem.
· Lastly, some rubies display a wonderful silky shine, called ‘silk’ of the ruby. This is caused by very fine needles of rutile. Sometimes, the retiles create the fabulous star rubies.

A really perfect ruby is rarer than perfect love. And it is the costliest gem on earth. Even costlier than diamond.

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Sapphire http://binoygupta.com/nature/sapphire-25/ http://binoygupta.com/nature/sapphire-25/#comments Tue, 12 Feb 2008 12:25:14 +0000 http://binoygupta.com/?p=25 Read more ›]]>


The Blue Gemstone – Another Prince of Gems
I am sure you would like to know more about the gem stones.
This informative article is one of a series of 5 articles covering the four precious gemstones – Diamond, Ruby, Sapphire, Emerald and Pearls (which is really not a gem).

Which colour would you associate with Sapphire?
The answer is pretty obvious. Blue.

Most people believe that all sapphires are blue.
It is true that the best and most precious sapphires are blue.
But sapphires extend over a wide range of colours except red.

Sapphire is a form of Corundum

Chemically, sapphire is corundum, a crystalline form of aluminium oxide, found in nature as a mineral.
In this photograph, you can see a piece of natural corundum.
Corundum is the second hardest mineral on Earth (the hardest is diamond).

On the Mohs scale (which is a measure of hardness), the score of corundum is 9.
It is so hard that combined with other additives, it is used as an abrasive – from the common sand paper to large machine tools for machining anything from metals to the hardest stones.
Pure corundum is colourless.

Traces of other elements like chrome, iron, titanium or vanadium give it colour.
What is a Sapphire

Both sapphire and ruby are corundum, that is, aluminium oxide.
Their colours are different because of the presence of different trace elements.

A trace of chrome makes the gem red and it is called ruby.

Only red corundum can be called ruby.
Traces of iron, titanium or vanadium give the corundum different colours.

Corundum of all colours, other than red, are classified as sapphires.

Different kinds of Sapphires

Star Sapphires

Star sapphires contain intersecting needle-like inclusions (usually rutile, a mineral composed mainly of titanium dioxide).When viewed under a single overhead light source, the sapphire will display a six-rayed ‘star’.
Blue sapphires
Deep and vivid blue sapphires are the most in demand.
Sapphire and India

The finest sapphire in the world, having the most intense and vivid blue hue (Kashmir Blue) originated from India’s north western region of Kashmir, along the Indo Pakistani border, in the Himalayas.

A landslide caused by an earthquake in the late 1800’s revealed sapphires in that region.

The region was excessively mined for eight years.

By the early 1900s, the region was completely depleted.

Where do the finest Sapphires come from
Sapphire and Ruby Mines of Mogok

After Kashmir, the world’s finest sapphires, rubies and spinels have been found in the Mogok Stone Tract of the high-altitude Mogok Valley, about 175 km northeast of Mandalay, in Myanmar (Burma).
The 4,800 square kilometer area, comprising the Mogok Valley, has over 1000 ruby and sapphire mines. In 1972, the world’s largest sapphire (63,000 carats) was found in the Mogkok valley.
But some of the finest sapphires have come from Sri Lanka.

Both the Logan sapphire and the Star of Bombay came from Sri Lanka.

Today, Madagascar is the world leader in sapphire production.

Some fabulous Sapphires

The 182 carat (36.4 g) Star of Bombay, is one of the world’s greatest blue star sapphire.
Douglas Fairbanks, Sr., the actor, gave it to his wife, the silent-film actress Mary Pickford.

It is now housed in the National Museum of Natural History, Washington D.C.
The massive 563.35 carat Star of India is the largest sapphire in the American Museum of Natural History.

But its colour is not deep, but a grayish blue.


The giant 423 carat Logan Sapphire set with 20 diamonds is the largest sapphire in the Smithsonian collection.

The stone has a rich blue color, but unfortunately is faceted with a large window.
Synthetic Corundum
Big and beautiful sapphires can be made artificially.

In 1903, Verneuil produced high quality synthetic corundums on a commercial scale by using a flame fusion process.

This simple and inexpensive process is used to produce flawless single crystal sapphires, rubies and other corundum gems of much larger size than are normally found in nature.

The Verneuil Process has been replaced by the Flux-Grown method which produces large, high-quality gem-grade sapphire.
Synthetic sapphire crystals of large size, up to many inches in diameter, can be grown in cylindrical crystal boules.

On the right, you can see a ring with a synthetic star sapphire.
Improvements
Natural sapphires are usually heat treated to improve their appearance and color.

Heat treatment improves the sapphire’s color and clarity.

Many natural sapphires are also diffusion treated.

In this process, trace elements are added to impart or to improve colors.
The sapphire is a prized possession.

A sapphire which suits its owner is supposed to bring very good luck.

And a sapphire which does not suit its owner could bring extreme misfortune.

Prospective purchasers often test its suitability by keeping it under their pillow.

Good dreams mean it is suitable for them.

Bad dreams indicate that they should not purchase the sapphire.

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