The influence of the intensity of melt stirring on the radial impurity distribution and optical quality of proustite single crystals grown by the Stockbarger method using ACRT is studied by the example of Cu, Sb and Mg impurities. We report results obtained in a wide range of Taylor numbers (1.9 x 10(5) < Ta < 7.12 x 10(7)). The studies revealed that the ACRT can be applied validly to decrease the impurity content during the growing of high-quality single crystals.' (C) 2003 Elsevier Science B.V. All rights reserved.