Transparent, colorless low-titania beta-quartz glass-ceramic material

A transparent, essentially colorless glass-ceramic material, comprising a β-quartz solid solution as a predominant crystalline phase, having a composition, expressed in terms of weight percentages on a basis of oxides, consisting essentially of:

• SiO2:
• >65-71
• Al2O3:
• 19-23
• Li2O:
• 3-4
• B2O3:
• 0-1
• TiO2:
• 0.3-<1.6
• SnO2:
• 0.25-1.2
• TiO2+SnO2:
• <1.8
• CeO2:
• 0-0.4
• WO3+MoO3:
• 0-<1
• CeO2+WO3+MoO3:
• 0-<1
• Nb2O5:
• 0-0.6
• ZrO2:
• 2.2-3.8
• ZrO2+TiO2+SnO2:
• >3.0-<4.8
• MgO:
• 0-2
• ZnO:
• 1-4
• SrO:
• 0-2
• BaO:
• 0-1.8
• P2O5:
• 0-3
• K2O+Na2O:
• 0-1.5
• Gd2O3+La2O3+Ta2O5+Y2O3:
• 0-4
• Nd2O3+Er2O3:
• 0-0.08
• Fe2O3:
• <0.03;
• and
• free of arsenic oxide and antimony oxide, with the exception of unavoidable traces thereof.