Analytical solution of the problem of dissolved gas segregation from melt during the crystallization process was found. The problem was solved using 3 most commonly used geometries of crystal growth: plane, cylindrical and spherical. Shrinkage of the melt during crystallization was correctly taken into account. It was shown that in the case of equilibrium crystallization the solution becomes self-similar. The criteria allowing to predict the conditions for inevitable formation of cavities in solidified material is shown. (C) 2017 Elsevier Ltd. All rights reserved.