Ice-nine is a fictional material conceive by science fiction writer Kurt Vonnegut in his novel Cat's Cradle. It is supposed to be a more stable polymorph of water than common ice (Ice Ih) which instead of melting at 0° Celsius (32° Fahrenheit), melts at 45.8°C (114.4°F). When ice-nine comes into contact with liquid water below 45.8°C, it acts as a seed crystal, and causes the solidification (freezing) of the entire body of water which quickly crystallizes as ice-nine.