Abstract: A glass composition includes oxides which form non-volatile fluorides at a temperature of 150° C. and a pressure of 5 Pa or less and are present in an amount of less than 0.5 mol % in the glass composition, based on all oxides present in the glass composition. A working point of the glass composition is 1400° C. or less. The glass composition has a hydrolytic resistance characterized by a leachability of GeO2, P2O5 and/or B2O3 from the glass composition determined as concentrations in an eluate prepared according to ISO 719 of at least one of the following: less than 70 mg/l GeO2 in the eluate per 1 mol % GeO2 in the glass composition; less than 70 mg/l P2O5 in the eluate per 1 mol % P2O5 in the glass composition; or less than 300 mg/l B2O3 in the eluate per 1 mol % B2O3 in the glass composition.