Monday, August 31, 2015

Sapphires belongs to the corundum group, the members of which are characterised by their exceptional hardness - second only to the Diamond, the hardest mineral on earth.This group of gemstones crystallised as a result of pressure and heat at a great depth. The presence of small amounts of other elements, especially iron and chrome, are responsible for the coloring, which can be blue, red, yellow, pink, purple or greenish. Recently, it has become the accepted practice that only ruby-red ones are called 'rubies' and all others be called Sapphire. Within each broad color category are many variations. For example there is an orange variety with a fine pink undertone which is called 'padparadscha', which means something like 'lotus flower'.
Top-quality sapphires are rare. Sapphires are found in India, Burma, Ceylon, Thailand, Vietnam, Australia, Brazil and Africa. From the gemstone mines, the raw crystals are taken to cutting-centres. It takes skill to cut an exceptional Sapphire because, not only are the stones hard, but depending on the angle from which you look at them they also have different colours and intensities of colour. So the cutter must orientate the raw crystals stone so that the best color is brought out. Kashmir Sapphires are the most highly valued for their unique color- a pure, intense blue with a very subtle violet undertone. the Burmese is also well regarded for a rich royal a deep cornflower blue. Sapphires value depends on size, colour and transparency as well as whether the color is natural or treated.
A selection of both rough and cut Kashmir sapphires.
The cut stones range from 6-14 ct.
(Photo: Henry Hänni/SSEF)

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