Some facts about the Cat’s Eye

Chrysoberyl is a mineral made of aluminum oxide and beryllium and is usually a translucent yellow-green stone.

Sometimes the chrysoberyl stone can be in the color yellow or green (which turns to red). The stone is then classified as two different types of gemstones.

Alexandrite gemstone

If the Chrysoberyl has a color which is ‘green to bluish-green in daylight’ but turns to a soft pastel ‘shade of red or purplish-red in incandescent light,’ it is known as the Alexandrite gemstone.

Cat's Eye gemstone (Cymophane)

If the Chrysoberyl has a translucent yellowish color it is known as a cymophane or cat’s eye gemstone.

Cymophane is called a ‘cat’s eye’ because of the unique band of light which goes across the gem from one end to the other. This rare phenomenon can only be seen on a cat’s eye gemstone and is referred to as chatoyancy. Chatoyancy is an ‘optical reflectance effect’ which is common trait in some gemstones.

The chatoyancy effect on a cat’s eye is remarkable when light is displayed on the gem.The gem will have a milky color appearance in the center and a yellow color on either side but as its being turned while the light is shining on it, the gem will appear as though it’s ‘opening and closing similar to that of an eye.’

The cabochon cut (dome-shape cut) is the recommended cut for a cat’s eye gemstone for it helps to bring out the cat’s eye effect of the gem. The cat’s eye effect is due to the presence of ‘parallel inclusions of tubes/fibers’ in the gem.

The best cat’s eyes are the ones which are termed ‘milk and honey.’ Such gems will have a honey color or lemon color to it with the band of light in the center similar to a milky white color.

The Duke of Connaught is credited for popularizing the cat’s eye in the late 19th century when he used it in an ‘engagement token’ which he gifted to the princess of Prussia.

The Cat’s Eye gemstone has been linked to folklore since ancient times. In Sri Lanka some people wear it to ward off evil spirits. In some other cultures the gem is believed to bring good luck, harmony, peace of mind and improve self confidence to the one who wears it.

In Indian astrology the cat’s eye is linked to the planet Ketu, a planet associated with ‘spiritual enlightenment.’

Many gemologists claim the finest cat’s eyes are from Sri lanka although the gem is also mined in India, Brazil, Burma and Madagascar.

Sri Lanka

One of the largest chrysoberyl cat’s eyes in the world was discovered in Sri Lanka in the 1800’s.

It weighed 465 carats and was given the name 'The Eye of the Lion' by the family of King Rajasinghe I.

Other chrysoberyl cat’s eye which originated from this tiny island in the Indian ocean were:

The Hope Cat’s Eye weighing close to 500 carats.

The British Royal Jewel worn by Edward VII, George V, Edward VIII, and Queen Elizabeth II with a weight of 105 carats.

Ray of Treasure chrysoberyl cat’s eye housed at the National Gem and Jewelry Authority (NGJA) in Sri Lanka and weighs 103 carats.

The “Maharani” chrysoberyl cat’s-eye weighing 58.2 carats.

It is kept at the Smithsonian National Museum of Natural History in Washington, D.C.

The Cat’s eye is an 8.5 on a Mohs scale.

A Moh’s scale is used to measure the hardness and durability of a gemstone/mineral.

© 2012 Suranee Perera