Abstract: Based on the experiments, some coloration phenomena in PbWO₄ crystals grown from the mixture of PbO and WO₃ powders by a modified Bridgman method were reported. Through analyzing these experimental phenomena, it was proposed that both defects of VO and VPb exist in the PbWO₄ crystals, and that Vo leads to the decrease of transmission at 350nm whereas the existence of VPb is the main cause which results in the coloration of the crystal and absorption band at 420nm.

Key words: PbWO₄ crystal, coloration, crystal defects