Patent ID: 7179763

Claim:
A gray glass composition of the soda-lime-silicate type having an overall light transmission under illuminant A (T LA ) greater than 67 for a glass thickness equal to 3.85 mm, comprising the constituents below within the following limits by weight: SiO 2 64–75% Al 2 O 3 0–5% B 2 O 3 0–5% CaO 5–15% MgO 0–5% Na 2 O 10–18% K 2 O 0–5% and the coloring agents below within the following limits by weight: Fe 2 O 3 0.25–0.65% CoO less than or equal to 10 ppm NiO 40–250 ppm Se 0–5 ppm where Fe 2 O 3 is the total iron.