Silica is the main constituent of glass. But it is to be added with sodium potassium carbonate to bring down melting point. To make it durable lime or lead oxide is also added. Manganese oxide is added to nullify the adverse effects of unwanted iron present in the impure silica. The raw materials are ground and sieved. They are mixed in specific proportion and melted in furnace. Then glass items are manufactured by blowing, flat drawing, rolling and pressing.

Important Properties of Glass

1. It absorbs, refracts or transmits light. It can be made transparent or translucent.

2. It can take excellent polish.

3. It is an excellent electrical insulator.

4. It is strong and brittle.

5. It can be blown, drawn or pressed.

6. It is not affected by atmosphere.

7. It has excellent resistance to chemicals.

8. It is available in various beautiful colours.

9. With the advancement in technology, it is possible to make glass lighter than cork or stronger than steel.

10. Glass panes can be cleaned easily.