5 Pesos

Argentina's nickel-clad steel coinage of the early 1960s was partly a response to chronic peso devaluation that had rendered smaller denominations economically pointless. The 5 Pesos sat at a denomination that actually bought something when first struck, then watched that purchasing power evaporate across its seven-year run as inflation averaged above 20% annually through the Frondizi and Illia governments.

The shift to nickel-clad steel reflected a deliberate cost-reduction policy — the Banco Central had already cycled through several alloy changes in the prior decade chasing the same goal.