Abstract: An infrared and ultraviolet absorbing soda-lime-silica glass of a neutral tint containing 0.3% to 0.7% by weight total iron expressed as Fe2O3, together with amounts of Se, Co3O4 and a ferrous iron content to provide a ratio of ferrous iron to total iron in the range of 21 to 34. NiO and TiO2 may be added to the glass. The resultant glass, in a nominal 4 mm thickness, has a visible light transmission of at least 70% and a direct solar heat transmission at least 12 percentage points below the visible light transmission. The iron in the glass is preferably provided by the inclusion of the mineral wuestite in the glass batch formulation.

Abstract: An infrared and ultraviolet absorbing soda-lime-silica glass of a neutral tint containing 0.3% to 0.7% by weight total iron expressed as Fe2O3, together with amounts of Se, Co3O4 and a ferrous iron content to provide a ratio of ferrous iron to total iron in the range of 21 to 34. NiO and TiO2 may be added to the glass. The resultant glass, in a nominal 4 mm thickness, has a visible light transmission of at least 70% and a direct solar heat transmission at least 12 percentage points below the visible light transmission. The iron in the glass is preferably provided by the inclusion of the mineral wuestite in the glass batch formulation.

Abstract: Radiation stable glass for space applications, especially glass in the form of thin sheet for cladding of spacecraft, is produced by including at least 5% by weight of barium oxide in a borosilicate glass composition. Because barium has a low absorption in the ultra violet, its use enables radiation stable glasses of low ultra violet absorption to be produced, alleviating problems of overheating when the glasses are used for cladding space craft. The glass is useful in the production of solar cell cover slips and second surface mirrors for cladding purposes, and space applications generally.

Abstract: Radiation stable glass for space applications, especially glass in the form of thin sheet for cladding of spacecraft, is produced by including at least 5% by weight of barium oxide in a borosilicate glass composition. Because barium has a low absorption in the ultra violet, its use enables radiation stable glasses of low ultra violet absorption to be produced, alleviating problems of overheating when the glasses are used for cladding space craft. The glass is useful in the production of solar cell cover slips and second surface mirrors for cladding purposes, and space applications generally.

Abstract: A method of making glass in which a first glass composition is fed to a furnace and the densities of such glass is determined. The composition is then changed to produce a second glass which has substantially different properties from the first glass, the change to the composition being such that the desired properties are produced in the second glass while simultaneously maintaining the densities of the second glass substantially equal to that of the second glass. The first glass may be a clear glass while the second glass may be a tinted glass. In such a case, the tinted glass may contain iron and the densities are maintained substantially equal by utilizing the iron to replace calcium oxide in the clear glass composition.