A single crystal boule of cubic Gd3Ga5O12 garnet doped with Nd, which was grown by the Czochralski technique, was optically examined by using microscopic and Sénarmont methods. The crystal contained deformed zones and consequently showed the striations interleaved with undeformed zones. The zonal striations show the convex shape parallel to one another and are nearly perpendicular to the [111] growth axis. The birefringence of the deformed zones was estimated as 10-6 in the order of magnitude. The axis for large refractive index is nearly parallel to the growth axis, while the axisfor small one is nearly parallel to the striations, though the axes are slightlyinclined at point to point of the striations. The distribution of birefringence along the striations was analyzed to be larger from the core towards outer periphery of the crystal boule.
