Sunday, 16 March 2014
CAT'S EYE GEM STONE AND IT'S INFORMATION.
Translucent yellowish chatoyant chrysoberyl is called cymophane or cat's eye.
Cymophane has its derivation also from the Greek words meaning 'wave' and 'appearance',
in reference to the chatoyancy sometimes exhibited. In this variety, microscopic tube like
cavities or needlelike inclusions of rutile occur in an orientation parallel to the
c-axis producing a chatoyant effect visible as a single ray of light passing across the
crystal. This effect is best seen in gemstones cut in cabochon form perpendicular to the
c-axis. The color in yellow chrysoberyl is due to Fe3+ impurities.
Although other minerals such as tourmaline, scapolite, corundum, spinel and quartz can
form "cat's eye" stones similar in appearance to cymophane, the jewelry
industry designates these stones as "quartz cat's eyes", or "ruby cat's eyes"
and only chrysoberyl can be referred to as "cat's eye" with no other designation.
Cymophane has its derivation also from the Greek words meaning 'wave' and 'appearance',
in reference to the chatoyancy sometimes exhibited. In this variety, microscopic tube like
cavities or needlelike inclusions of rutile occur in an orientation parallel to the
c-axis producing a chatoyant effect visible as a single ray of light passing across the
crystal. This effect is best seen in gemstones cut in cabochon form perpendicular to the
c-axis. The color in yellow chrysoberyl is due to Fe3+ impurities.
Although other minerals such as tourmaline, scapolite, corundum, spinel and quartz can
form "cat's eye" stones similar in appearance to cymophane, the jewelry
industry designates these stones as "quartz cat's eyes", or "ruby cat's eyes"
and only chrysoberyl can be referred to as "cat's eye" with no other designation.
RUBY STONE AND AND IT'S INFORMATION.
A ruby is a pink to blood-red colored gemstone, a variety of the mineral
corundum. The red color is caused mainly by the presence of the element
chromium. Its name comes from ruber, Latin for red. Other varieties
of gem-quality corundum are called sapphires. The ruby is considered one of the four
precious stones, together with the sapphire, the emerald and the diamond.
Prices of rubies are primarily determined by color.
The brightest and most valuable "red" called blood-red, commands a large
premium over other rubies of similar quality. After color follows clarity.
similar to diamonds, a clear stone will command a premium, but a ruby without
any needle-like rutile inclusions may indicate that the stone has been treated.
Cut and carat (weight) are also an important factor in determining the price.
corundum. The red color is caused mainly by the presence of the element
chromium. Its name comes from ruber, Latin for red. Other varieties
of gem-quality corundum are called sapphires. The ruby is considered one of the four
precious stones, together with the sapphire, the emerald and the diamond.
Prices of rubies are primarily determined by color.
The brightest and most valuable "red" called blood-red, commands a large
premium over other rubies of similar quality. After color follows clarity.
similar to diamonds, a clear stone will command a premium, but a ruby without
any needle-like rutile inclusions may indicate that the stone has been treated.
Cut and carat (weight) are also an important factor in determining the price.



