A number of lanthanide-doped ZnO materials, such as composites, films, nanoparticles etc., has already been reported in literature . However, it's still unclear whether large number of lantanide ions can be dispersed in ZnO crystalline lattice or the ions can only segregate into crystalline lanthanide oxide due to large charge and radius of trivalent lanthanide ion. Such thermodynamically non-equilibrium method as ion-beam implantation results in the incorporation of lanthanide ions in ZnO crystalline lattice with its subsequent out diffusion and segregation upon heat treatment . That fact also raises a question whether the luminescent lanthanide centers located in ZnO matrix or at interface between zinc and lanthanide oxides . This work is a follow-up of our previous article on ZnO single crystal growth via spontaneous crystallization from high-temperature melts under high pressure . In that work, the grown ZnO single crystals (up to several millimeters) exhibited strong luminescence in the UV and visible ranges. In the present work, the crystal growth method was adapted for growing a mixture of poly-and single crystals of ZnO and Yb 2 O 3 , and the recovered samples were studied by scanning electron microscopy (SEM), X-ray diffraction and cathodoluminescence spectroscopy.