Ice IX
Ice as the lay person would know it, is known as ice-I (in the Bridgman nomenclature).
Different types of ice, from ice-II to ice-IX have been created in the laboratory at different temperatures and pressures.
Ice IX is not to be confused with "Ice-9" a fictional discovery in the novel Cat's Cradle by Kurt Vonnegut, Jr..
References
Bridgman, P. W. (1937) J. Chem. Phys. 5, 964.
