Ice VII is a more stable polymorph of water than common ice (Ice Ih) which instead of melting at 0 degrees Celsius (32 degrees Fahrenheit), melts at 45.8 °C (114.4 °F). When ice VII comes into contact with liquid water below 45.8 °C (which is thus effectively supercooled), it acts as a seed crystal, and causes the solidification of the entire body of water which quickly crystallizes as ice VII. Aware of the dangers of this substance, when it was synthesized in secret by French scientists in the 1960s, the substance was disposed of by melting the substance. The files have, however, been kept locked away for continued study.