Why are dimes comparatively the smallest coin in most currencies?

Answer 1

Dimes were the lowest denomination coin to be made from precious metal (silver), supposedly at order of the Continental Congress of 1786. Prior to 1965 US dimes had .07 troy ounce of silver, one tenth the weight of a silver dollar. The primary content of lower denomination coins is copper or steel, which allows them to be a larger size, although at times the cost of producing pennies has exceeded their value.