The growth of BaSO4 from high-temperature fluxes of both chloridic alkaline metal and alkaline-earth metal solvents has been investigated. Two binary alkaline-metal solvent systems containing LiCl and the additive ternary system with CsCl-KCl-NaCl where optimized with respect to solute concentration and growth temperature. It is found that the solution of BaSO4 in these solvents increases with decreasing average radius of the solvent cation. In addition, the solubility of BaS04 is increased in the LiCl-containing fluxes by a chemical reaction between solute and solvent. Binary solvents of LiCl-KCl and LiCI-CsCl delivered prismatic crystals of 2 cm size, whereas the CsCl-KCl-NaCl flux prefers the growth of short-prismatic crystals. The crystals grown under optimized conditions were crack free, colorless, and transparent. (C) 2002 Elsevier Science B.V. All rights reserved.