The solubility data of emerald in H2SO4 aqueous solution under hydrothermal conditions were measured by using the "quenching-weighing" method. The relationship of S-T-C at a constant filling level 60% shows that the emerald has a large solubility (S) and a large temperature coefficient of the solubility (dS/dT) in H2SO4 solvent enough for hydrothermal growth of crystals. These studies helped us to grow several emerald crystals of good quality under hydrothermal conditions. (C) 2002 Elsevier Science B.V. All rights reserved.