Sunday, December 23, 2007

Ruby




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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