Colored glass compositions and glazings produced therewith

A glass composition for forming colored glazings consisting essentially of, in percent by weight, 64 to 75% SiO.sub.2, 5 to 15% CaO, 10 to 18% Na.sub.2 O, at least one of Al.sub.2 O.sub.3, B.sub.2 O.sub.3, MgO or K.sub.2 O, each in an amount of up to 5% by weight and CoO as a coloring agent in an amount of up to 0.05% by weight, wherein the amount of CoO is greater than about 0.02% by weight when Fe.sub.2 O.sub.3 is present in said composition in an amount less than 2% by weight, and selenium in an amount up to about 0.005%, and as a coloring agent, 1.4 to 4% Fe.sub.2 O.sub.3, wherein the amount of alkaline earth oxides is between about 6-16% by weight and the amount of alkali metal oxides is between about 10-20% by weight and wherein glazings formed of said composition when illuminated under Illuminant C, has a dominant percentage light transmission between about 485-570 nm, and which have a total light transmission factor under illuminant A of less than 20% and a total energy transmission factor of less than 12% when said glazings have a thickness of about 3.85 mm.