Well-formed crystals of emerald, Be3Al2Si6O18 : Cr, were easily grown from an Na2OMoO3 flux by an isothermal technique. The crystal growth was conducted by heating a mixture of solute and flux at 1 100 ℃ for 24 h. The evaporation loss of flux depended on the amount of Na2O added to MoO3. Emerald crystals of lengths up to 2. 1 mm and widths of 1.4 mm were grown. The crystal sizes were dependent on the evaporation loss of the flux. The obtained crystals were transparent and exhibited the typical emerald-green color. The form of the emerald crystals was a twelve-sided prism bounded by well-developed faces. The aspect ratios were in the region of 1.4 to 2.3. The density was (2.64±0.02)g/cm3. The IR absorption bands were in good agreement with the literature data.