Its because the sliver is expensive than copper or aluminium.
Harsh Singla answered this
It is too expensive than copper and aluminium
Vansh Mehta answered this
IT IS BECAUSE COPPER AND ALLUMINIUM ARE NOT SO EXPENSIVE WHEREAS SILVER IS SO EXPENSIVE.
Siddharth Mallisetti answered this
no offense but can i ask u something .do u consider copper and aluminium to be held to buy in jewllery shops . where can ufind so much silver .silver is a lot more precious and rare thancopper and aluminium