But Europe and Asia lag in the development of coatings,'' says Robert Heintges of R. A. Heintges Architects Consultants. Molten silica is poured onto a bed of molten tin, where it remains until it hardens. The result is glass that is perfectly flat and clear. Rolling the glass in a semimolten state creates patterns. Introducing various additives to the silica produces colors, tints, and other effects.
Cobalt oxide turns glass blue.
Cobalt and nickel neutralize other metals and make glass colorless. Iron produces an aquamarine cast but adds strength. Reducing the amount of iron creates glass that is less reflective and therefore appropriate for retail applications. Phosphorus makes glass opalescent. Many companies have their own formulas for achieving different effects.