ECU Europa; 9 countries; gold

The ECU — European Currency Unit — was a basket currency introduced by the European Monetary System in 1979, weighted across member state economies but never issued as legal tender for general circulation. These gold pieces were struck by the Monnaie de Paris as collector issues, not monetary instruments, though the ECU itself underpinned exchange rate mechanisms that would eventually inform the architecture of the euro. The nine countries reflected EMS membership before Greece's 1981 accession expanded the bloc.