It is connected with planet Saturn. The metal it is associated with is silver. It rules over teeth, feet, bones, knees,nerves and nails. It can be worn by those whose ascendant is Taurus, Libra,virgo,gemini and Capricorn.
Cat's-eye is the gemstone recommended for Ketu; specifically Chrysoberyl cat's-eye. The finest quality is called "milk and honey", as the stone is a honey color, with the eye white, like milk. The darker varieties are generally a greenish body color and still very powerful in their effect.
Dark, especially black imperfections should be strictly avoided in this stone (as with most others) as wearing such a stone can cause early demise, as several ancient texts state. The source countries for cat's-eyes are India, Burma, Sri Lanka and Brazil.
Cat's-eye is said to increase powers of perception and insight. It should also give greater discrimination in action. The ancients believed that cat's-eye protected individuals from epidemics or diseases, from drowning and from enemies, as well as heightening psychic perceptions. Coincidentally it is supposed to bring good fortune to gamblers. Apatite cat's-eye may be a less costly substitute for cat's-eye Chrysoberyl, although its effects are less powerful, as well.