  The melting of pure axisymmetric ice crystals has been described previously
by us within the framework of so-called geometric crystal growth.
Nonequilibrium ice crystal shapes evolving in the presence of hyperactive
antifreeze proteins (hypAFPs) are experimentally observed to assume ellipsoidal
geometries ("lemon" or "rice" shapes). To analyze such shapes we harness the
underlying symmetry of hexagonal ice Ih and extend two-dimensional geometric
models to three-dimensions to reproduce the experimental dissolution process.
The geometrical model developed will be useful as a quantitative test of the
mechanisms of interaction between hypAFPs and ice.
