The influence of supersaturation oil the evolution of crystal faces is analysed. The changes in evolution of crystal faces are estimated based on tangential growth rate. Various values of this rate correspond to increase, decrease or preservation of the size of a given face. The results show that even small fluctuation in supersaturation may lead to rapid change in the evolution of a given face. The influence of the fluctuation in supersaturation is the most significant for faces, which form small interfacial angles. Theoretical predictions are compared with experimental data for potassium dichromate (KBC) crystal. Theoretical and experimental results agree very well. (c) 2006 Elsevier B.V. All rights reserved.