Monday, November 28, 2011

Diamond


The word diamond comes from the Greek word meaning unbreakable.

Most diamonds found in nature are between one to three billion years old.

Most diamonds are found in volcanic rock, called Kimberlite, or in the sea after having been carried away by rivers when they were pushed to the surface.

Also, diamonds have been found in some meteorites and the impact of meteorites with Earth is thought to produce enough heat and pressure to transform carbon into diamonds.

Diamonds are so hard that the only tool that can be used to cut a diamond must be made from another diamond.

Harvard physicist Peter Lu and colleagues found that ancient Chinese used diamonds to polish ceremonial burial axes in the late stone age or over 4,500 years ago.

Diamonds were discovered in India at least 2400 years ago and India was the first commercial producer of diamonds. The country dominated commercial diamond production until South American discoveries in the 1730's.

Around 26,000 kilograms (57,000 lb) of diamonds are mined around the world every year. They are worth billions of dollars to the powerful companies that control their production.



Diamonds actually are found in abundance; thousands are mined every year. 80% of them are not suitable for jewelery – they are used in industry or in cheap rings.

The value of a diamond is based upon its Carat weight, Clarity, Color and the quality of its Cut. Most diamonds are in a color range that runs from clear to yellow to brown. Those that are colorless receive the highest grade and are generally of highest value.



A small number of natural diamonds fall outside of the typical white-yellow-brown color range. They can be pink, blue, purple, red, orange or any color. When they are a pleasing shade they can be extremely valuable and are given the name "fancy" diamonds.

















The world’s largest diamond was the Cullinan, found in South Africa in 1905. It weighed 3,106.75 carats uncut. It was cut into the Great Star of Africa, weighing 530.2 carats, the Lesser Star of Africa, which weighs 317.40 carats, and 104 other diamonds of nearly flawless color and clarity. They now form part of the British crown jewels.





The tradition of a diamond engagement ring started in 1477 when Archduke Maximillian of Austria gave a diamond ring to Mary of Burgundy.




The modern tradition is the result of a clever advertising campaign designed by N.W.Ayer in the 1940s, a marketing gimmick still used today. The fact is that most diamonds have little resale or investment value.



The world’s Biggest Hole is actually a diamond mine in Eastern Siberia   (Yakutia) near the town Mirny in Russia. It is 525 meters deep and 1.25 km in diameter. Flying of helicopters and other planes over the hole has proved to be risky due to the suction produced by its depth!


Today, the top seven diamond-producing countries, accounting for 80 percent of the world’s rough diamond supply, are Botswana, Russia, South Africa, Angola, Namibia, Australia and Zaire.