Glass comprises essentially 20-70% SiO₂, 10-50% TiO₂+Nb₂O₅+SnO₂+Ta₂O₅+WO₃+CeO₂, 0-50% MgO+CaO+SrO+BaO+ZnO, and 0-30% B₂O₃+Al₂O₃, in molar percentage terms based on the oxides; and has a resistivity of at most 10¹⁵ cm at 20 C. A method for production of glass is to produce the glass under such a condition that a redox represented by [Fe²⁺]/([Fe²⁺]+[Fe³⁺]) where Fe is present in the glass, is at least 0.6.