In the method and system for producing glass reduction of reduction-sensitive ingredients in the glass is reduced or preferably is avoided during the melting and fining processes. The glass preferably has a high refractive index. During the process an oxidizing agent is inducted into a fining vessel and preferably also into a melt crucible made of a slit skull that is cooled by a cooling agent. The oxidizing agent is preferably oxygen. Furthermore a system for conducting the method is also described.