Rocky Mountain (56th Annual) and Cordilleran (100th Annual) Joint Meeting (May 3–5, 2004)

Paper No. 13
Presentation Time: 8:00 AM-5:00 PM


KIM, Won-Sa, Dept. of Geology, Chungnam National Univ, Taejon, 305-764, South Korea,

An yttria-stabilized zirconium oxide crystal has been synthesized by the skull melting method. Gem-quality colorless and transparent materials is produced when 25wt.%Y2O3(stabilizer) and 0.04wt.%Nd2O3(decolorising agent) are added to the ZrO2 powder. It shows vitreous luster with a slightly oily appearance. Under a polarizing microscope, the crystal shows isotropic nature with no appreciable anisotropism. Mohs hardness value and specific gravity is measured to be 8 and 5.85, respectively. Under ultraviolet light it shows a faint white glow. The crystal structure of yttria-stabilized zirconia has been re-investigated using single crystal and neutron diffraction methods. The symmetry is cubic with space group Fm3m and a=5.1552(5)A, V=136.99(5)A3, Z=4. The stabilizer atoms randomly occupy the zirconium sites and there are displacements of oxygen atoms with amplitudes of ~0.033 and 0.11 along <110> and <111> from the ideal positions of the fluorite strucrure, respectively.