Question

Explain the following term.

Coloured glass

Answer 1

Coloured glass: The glass which has some colours in it is called coloured glass.

• Coloured glass is made by adding a small quantity of metallic oxides to the mixture of limestone or Calcium carbonate (CaCO₃), soda ash or Sodium carbonate (Na₂CO₃), and sand (SiO₂)
• The colour of the coloured glass is decided by the type of metallic oxide added to the mixture.
• Example: The addition of Nickel oxide (NiO) gives violet colour to the glass whereas the addition of Chromic oxide (Cr₂O₃) imparts emerald green colour to the glass.
• Coloured glass is used to make decorative items, sunglasses, and to make lights for signals in automobiles.