Precious stones: the sapphire
A little history...As the ruby, the sapphire belongs to the family of corundum. The most beautiful sapphires come mainly from the Kashmir(Cashmere), Sri Lanka, Myanmar (ex-Burma) or the Tanzania, we find also of less beautiful but in larger quantity in Cambodia, Kenya, China, Australia, Madagascar, Thailand or in the USA (Montana).
Among the more famous sapphires include the Star of India, probably the biggest star sapphire of 536 carats never cut and Midnight Star, a black star sapphire of 11 carats.
The sapphire symbolizes the faith, the truth, the sincerity and the loyalty in relationships, this gemstone is supposed to bring peace, joy and wisdom. it is probably for these reasons that the sapphire often adorns engagement rings. Throughout history, one used sapphire as a talisman against evil spirits and to protect travelers and researchers. The Persians believed that the earth rested on an immense sapphire the brightness of which gave the color of the sky and the Buddhists confer it powers facilitating the concentration and meditation and protection against the bad luck.
Its blue, celestial and sacred color, and the fact that this gemstone is repeatedly evoked in the Bible (the tables of 10 commands would be in sapphire) makes of the sapphire a episcopal stone very sought by kings and popes.
And to close this long list of beliefs on this stone, one also lend it the powers of cure of the rheumatisms, the protection against the stings of scorpions and snake bites, ' Stone of eyes ', he would preserve them from dust and impurities. One believed so much in its power of cure that in 17th century one used it to look after the wounds of lepers (gasp!).
ESTIMATING THE VALUE OF THE SAPPHIRE
As for the other precious stones, the value of the sapphire depends on its purity, this value falls according to the number of inclusions or if a colored veil appears or not. It is also necessary to judge its color, she must be lively and supported, but neither too pale and nor too much darkened. It is also necessary to take into account in this estimation the quality of the size and the developed treatments. Any stones has to have a certificate mentioning the characteristics of the stone, based on the usual techniques of expertise and on the application of international standards of gemology. In the same way as the diamond, we use the method of 4C: Color ( color), Clarity ( purity), Cut ( cutting) and Carat weight (weight in carat).
( See → the 4C of the diamond)
Click the photo to see an example of certificate and the various criteria of estimation.
The Tanzania as for it, ancient and renowned producer of sapphires of colors except the blue sapphires, begins too the production of this bluish gemstone after the discovery of deposits in the South.
The cutting with facets is generally reserved at the most beautiful sapphires. For the sapphires of less beautiful quality, possessing too many inclusions, lacking even opaque transparency and a too much darkened color, often it is the cut in form "cabochon" that is used. This the same cut "cabochon" that will reveal the beauty of star sapphires.