Zirconium hydride an ore, usually a zirconium silicate, such as zircon. Zirconium is extracted from zirconium ore by removing the oxygen and silica. This process, known as the Kroll process, was first applied to titanium. The Kroll process results in an alloy containing hafnium. The hafnium and other impurities are removed in a subsequent step. Zirconium hydride is created by combining refined zirconium with hydrogen. Like titanium, solid zirconium dissolves hydrogen quite readily. The density of zirconium hydride varies based the hydrogen and ranges between 5.56 and 6.52 g cm. Even in the narrow range of concentrations which make up zirconium hydride,
Cubic zirconia a strong, complex rare earth absorption spectrum. Discovered in 1892, the yellowish monoclinic mineral baddeleyite is a natural form of zirconium oxide. The high melting point of zirconia (2750 °C or 4976 °F) hinders controlled growth of single crystals. However, stabilization of cubic zirconium oxide had been realized early on, with the synthetic product "stabilized zirconia" introduced in 1929. Although cubic, it was in the form of a polycrystalline ceramic: it was used as a refractory material, highly resistant to chemical and thermal attack (up to 2540 °C or 4604 °F). In 1937, German mineralogists M. V. Stackelberg and K.