Disclosed are glass materials generally belonging to the P2O5—ZnO—TeO2 system and process for making the same. The glass may comprise Bi2O3 as well. The high refractive index and low Tg materials are particularly suitable for refractive lens elements for use in portable optical devices. The process involves the use of P2O5 source materials with reduced amounts of reducing agents or a step of removing the reducing agents from such source materials by an oxidizing step such as calcination.