Patent ID: 7585801

Claim:
A glass composition comprising a base glass composition comprising: SiO 2 65 to 75 weight percent, Na 2 O 10 to 20 weight percent, CaO 5 to 15 weight percent, MgO 0 to 5 weight percent, Al 2 O 3 0 to 5 weight percent, K 2 O 0 to 5 weight percent, and BaO 0 to 1 weight percent and a colorant and property modifying portion consisting essentially of: total iron 0.5 to 0.8 weight percent, Er 2 O 3 0.05 to 0.5 weight percent, Se 1 PPM to 4 PPM, CoO 1 PPM to 15 PPM, wherein the glass composition has a redox ratio ranging from 0.26 to 0.35.