abstract |
Bi-containing glass-ceramic material, especially those containing β-quartz and/or β-spodumene solid solutions as the predominant crystalline phase, and the precursor glass material as well as process of making such glass-ceramic material and articles. The glass-ceramic can be made to have a dark color, and essentially to be free of V 2 O 5 , As 2 O 3 and Sb 2 O 3 . |