Prabin Kalikote

Ceramic utensils are brought to use because:
    > It is insulator of heat and electricity.
    > It can resist high temperature.
    > It has resistant to the actions of chemicals.
    > It is hard and brittle.

Ceramics is a type of clay which contains the compounds of carbon, hydrogen, nitrogen, oxygen and silica.
It is produced by hydrated alumina silica. It contains other substance like limestone, magnesium carbonate, oxides of magnesia and iron.

Colored glass is prepared by adding certain metal oxides to the molten mass during the preparation of glass. Certain metal oxides impart a particular color to the glass. So, the selection of the metal oxide depends on the color of our choice.

The homogenous mixture of potassium silicate and lead silicate is called lead crystal glass.
It is used or making lens, prisms, electric bulbs, TV screens, etc.
Its characteristics are:
    > It has a high refractive index.
    > It has the presence of lead silica.

The homogenous mixture of sodium silicate, calcium silicate and boron silicate is called borosilicate (Pyrex) glass.
It is used for making laboratory apparatus like test tubes, flasks, breakers, ampules and other pharmaceutical containers.
Its characteristics are:
    > It is hard and does not melt at ordinary temperature.
    > It is strong than ordinary glass.
    > It is more resistant to heat and chemical.

Quartz glass is a pure crystalline glass which is prepared by heating silica at about 1600c and then cooling the products.

The materials used to make glass are listed below:
    > Mixture of silica: 25%
    > Pieces of glass: 25%
    > Sodium carbonate:15%
    > Calcium carbonate: 10%