What type of material is used as contact material in switches?

Copper is used as a substrate of the contact meterial; on the grounds of cost; but the actual contacts themselves may be made of silver. Silver does not corrode a badly as copper, and a well designed switch will have a 'wiping' action in its operation, for this prolongs the life of the contacts.

In corrosive atmospheres, such as Rotorua, New Zealand, there is a quantity of H2S in the atmosphere, and platinum contacts are often used.