Changes

==Manufacture==

==Manufacture==

Glass is produced industrially by heating a mixture of calcium carbonate (limestone), silicon dioxide (commonly known as sand) and sodium carbonate (soda) until it melts. The subsequent product, once cooled, is glass.

Glass is produced industrially by melting a mixture of calcium carbonate (limestone), sodium carbonate (soda), and silicon dioxide, which is a major component of sand. Quartz sand, which is rich in silicon dioxide, is the most commonly used type of sand. The subsequent product, once cooled, is glass.

==References==

==References==