How is Glass made?

Glass is made naturally from a mixture of Sand, Soda, and Lime. This fusion can be achieved merely by lightning, striking in a place where the right ingredients happen to be adjacent to each other. When glass is made by someone, other ingredients, such as potash, lead oxide and boric oxide are used to make glass clear, some to colout it, and others to give it a frosted effect.

There are four main methods of shaping glass: blowing, pressing, drawing, and casting. After the shaping process, annealing is used to restore the strength of the glass. Tempering and other finishing techniques may also be used to further strengthen the glass.

During the Roman Civilization, the art of glass-making reached near perfection. In the 3rd Century BC the Romans cast glass on stones and produced first window panes. After the breakup of roman empire, the glass making suffered as set back. Glazing of windows did not become wide spread over the whole of Europe until the 15th and 16th centuries.