Patent ID: 8056370

Claim:
A method for making ceramic comprising glass, the method comprising: contacting a melt with a surface of a rotating substrate such that the melt cools to provide a ceramic comprising glass, the melt comprising at least 35 percent by weight Al 2 O 3 , based on the total metal oxide content of the melt, a first metal oxide other than Al 2 O 3 , and a second, different metal oxide other than Al 2 O 3 , wherein the melt contains not more than 10 percent by weight collectively As 2 O 3 , B 2 O 3 , GeO 2 , P 2 O 5 , SiO 2 , TeO 2 , and V 2 O 5 , based on the total metal oxide content of the melt, and does not contain CaO; and the glass comprising at least 35 percent by weight Al 2 O 3 , based on the total metal oxide content of the glass, the first metal oxide other than Al 2 O 3 , and the second, different metal oxide other than Al 2 O 3 , wherein the glass contains not more than 10 percent by weight collectively As 2 O 3 , B 2 O 3 , GeO 2 , P 2 O 5 , SiO 2 , TeO 2 , and V 2 O 5 , based on the total weight of the glass, and does not contain CaO.