Casting the ATST Mirror (IMAGE) University of Arizona Caption Casting of a 4 meter mirror substrate made of "Zerodur" glass ceramic on June 2, 2006 at SCHOTT headquarters in Mainz, Germany. The molten glass is heated to more than 2,732 degrees Fahrenheit (1,500 degrees Celsius). After cooling and preliminary processing, the substrate is ceramized in an 11-month process in which the glass is transformed to glass ceramic. Credit SCHOTT Usage Restrictions Usage only permitted in conjunction with reporting/posting of this news release. Image credit must be included. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.