Growth of needlelike gypsum crystals from highly supersaturated aqueous sol
utions has been studied by the methods of the optical and electron microsco
pies. The average growth rates of the end faces and their fluctuations are
determined. It is shown that the fluctuations in the growth rates of end fa
ces are described by the Fokker-Planck equation and that the end faces of g
ypsum crystals grow by the layer mechanism with the layer nucleation in the
vicinity of one of the crystal vertices. (C) 2000 MAIK "Nauka/Interperiodi
ca".