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| Sapphire from Ural Mountains |
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More Sapphire on ebay auction |
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Sapphire www.gemstone.org Blue is Sapphire’s main colour. Blue is also the favourite colour of about 50 per cent of the population, men and women alike. This colour, which is strongly associated with sapphire, is also linked to emotions such as sympathy and harmony, friendship and loyalty. These emotions belong to features which are permanent and reliable – emotions where overwhelming and fiery passion is not the main element, but rather composure, mutual understanding and unshakeable trust. Sapphire blue has thus become a colour related to anything permanent and reliable, and this is one of the reasons why women in many countries settle on Sapphire for their engagement rings. Sapphire symbolises loyalty and faithfulness, while at the same time expressing love and yearning. The most famous musical example for this melancholic shade of blue can be found in George Gershwin’s "Rhapsody in Blue". Sapphire’s blue colour is also evoked where clear competence and controlled brainwork are the issue. After all, the first computer ever to wrangle a victory from a chess grandmaster and world champion was named "Deep Blue". en.wikipedia.org Sapphire includes any gemstone quality varieties of the mineral corrundum other than the red ruby. Sapphire is most commonly blue but also occurs as purple, yellow, orange, pink, green, color shift and white varieties. Sapphires have a hardness of 9 on the Mohs scale and do not cleave which makes them perfect for faceted gemstones. Blue sapphires come in a wide range of shades of blue. Titanium and iron inclusions within the aluminium oxide result in various shades of blue. Some stones are not well saturated and show tones of gray. About 90% of all sapphires are heated to a temperature of 3000 °C to give the stone a better color of blue. On magnification the silk due to included rutile needles are visible. If the needles are unbroken, then the stone was not heated. If the silk is not visible then the stone was heated adequately. If the silk is partially broken then a process known as low tube heat was used. Low tube heat is the process where the rough stone is heated to 1000 °C for 10 to 20 minutes. This takes out any gray in the stone and improves color saturation. Fancy sapphires are any sapphire other than blue or red. Purple sapphires are lower in price than blue ones. These stones contain the trace element vanadium and come in a wide variety of shades. Yellow and green sapphires have traces of iron which gives them their color. Pink sapphires are have trace element of chromium and the deeper the color pink the higher the value as long as the color is going toward red of rubies. Color shift sapphires are blue in outdoor light and purple in indoor light. Some stones shift color well and others only partially, in that some stones go from blue to blue purple. White sapphires usually come out of the ground as light gray or brown and are then heated to make them clear. However in very rare circumstances they will be found in a clear state. Sapphires are mined from alluvial deposits or from primary undergound workings. Historically, most sapphires have been mined in Sri Lanka, Madagascar and Myanmar. Australia, leads the world in sapphire production (as of 1987) specifically from basalt derived placer deposits in Queensland and New South Wales. Pakistan, Afganistan, India and Kenya also produce sapphires. The US state of Montana has produced sapphires from the Yogo Gultch deposit near Helena. |
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