US Patent 7560404 UV absorbing gray glass composition

A novel glass composition is disclosed. The glass composition includes a base glass composition made up of SiO2 from 65 to 75 weight percent, Na2O from 10 to 20 weight percent, CaO from 5 to 15 weight percent, MgO from 0 to 5 weight percent, Al2O3 from 0 to 5 weight percent, K2O from 0 to 5 weight percent, B2O3 0 to 5%, and MnO2 0 to 0.5%, and a colorant and property modifying material portion made up of total iron up to 0.65 weight percent, Se ranging from 2 PPM to 10 PPM, at least one UV absorber selected from CeO2, V2O5, TiO2 and MoO3, CoO up to 20 PPM, and Cr2O3 up to 75 PPM, wherein the glass composition has a redox ratio ranging from 0.2 to 0.6.