abstract |
Opal glass-ceramic with a continuous glass phase, a further glass phase discontinuously distributed in this continuous glass phase and a crystal phase of tetragonal leucite, characterized in that it consists of the following components: From 55.0% by weight to 66.0% by weight of SiO 2 , From 13.0% by weight to 23.0% by weight Al 2 O 3 , From 0% to 0.7% by weight of Sb 2 O 3 , From 0.1% by weight to 1.5% by weight of CaO, From 0% by weight to 0.3% by weight of BaO, From 8.0% by weight to 14.0% by weight of K 2 O, From 5.0% to 12.0% by weight of Na 2 O, From 0% to 0.2% by weight of Li 2 O, From 0.3% by weight to 0.5% by weight of P 2 O 5 , From 0% by weight to 1.5% by weight of B 2 O 3 , 0.1 wt.% To 1.0 wt.% F. |