Eutectic rods of Al 2 O 3 and Y 3 Al 5 O 1 2 were grown by a laser-heated float zone method, and their microstructure and crystallographic texture were studied by scanning electron microscopy, electron-backscattered diffraction and X-ray diffraction. The composites were found to be highly textured with two twin-related crystallographic orientation relationships between the phases. Electron-backscattered diffraction was employed to determine the spatial distribution of the orientational variants within the samples and to define the crystallographic orientation of various microstructural features.