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,
Crown (dentistry) cores are layered with tooth tissue-like feldspathic porcelain to make true-to-life color and shape. Dental artists called ceramists, can customize the "look" of these crowns to individual patient and dentist requirements. Today, porcelain fused to alumina crowns set the standard for tooth-like appearance. Yttria-stabilized zirconia, also known simply as zirconia, is a very hard ceramic that is used as a strong base material in some full ceramic restorations. Zirconia is relatively new in dentistry and the published clinical data is correspondingly limited. The zirconia used in dentistry is zirconium oxide which has been stabilized with the addition of yttrium oxide.