The three-carat cat's eye stone has been valued for millennia in many different cultures. It was thought to bestow luck and protection in classical Rome. A 3 carat cats eye stone, also called a lehsunia, is linked to the planet Ketu in Vedic astrology and is believed to guard off evil forces. Because of its alluring appearance and supposed magical qualities, the three-carat cat's eye stone has been valued throughout history.