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 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.

==References==

==References==