How Glass is Made

Video from PPG shows how sand is turned into glass

This video animation shows how sand is turned into glass with the help of limestone, dolomite, gypsum, and soda ash. Sand melts at 3000°F, but these added elements allow it to melt at a lower temperature. Once melted, the molten glass is transferred to a bath of molten tin. The glass floats on the tin, and becomes uniformly flat.