70 ECUs / 50 Pounds - Elizabeth II Charlemagne, facing left, gold .9999

Gibraltar's ECU-denominated gold issues of the early 1990s were produced specifically to capitalize on European monetary unification fever preceding the Maastricht Treaty, signed in February 1992. The ECU — European Currency Unit — was never legal tender in the conventional sense but existed as a basket currency for interbank settlement, which gave Gibraltar latitude to issue coins denominated in it as collectibles without violating any sovereignty agreements with the UK.

Charlemagne's selection was deliberate EC policy promotion: he had been invoked since the 1950s as a founding symbol of European unity, with the Karlspreis awarded in Aachen annually to figures advancing European integration.