Patent ID: 7754632

Claim:
A glass of soda-lime type composition, comprising: basic components in the following proportions by weight, SiO 2 66 to 75% Na 2 O 10 to 20% CaO 5 to 15% MgO 0 to 5% Al 2 O 3 0 to 5% K 2 O 0 to 5% and colouring elements in the following proportions by weight, Fe 2 O 3 1.1 to 1.5% (total iron in the composition) Co 150 to 200 ppm Cr 2 O 3 25 to 100 ppm Se 10 to 50 ppm MnO less than 600 ppm TiO 2 less than 0.1% wherein constituents of the composition are selected in such proportions that a luminous transmittance at a thickness of 4 mm, TLA4, is less than 20%, and an energetic transmittance, TE4 (Moon), is less than 20% and wherein a ratio of ferrous iron to total iron, representing a degree of oxidation of the composition, is: 0.20<Fe 2+ /total Fe<0.26.