20 ECU - Baudouin I 60th Birthday

The ECU — European Currency Unit — was never legal tender in the conventional sense; it existed as a basket currency used in European Community accounting and financial settlements from 1979 onward. Belgium was among its most enthusiastic institutional champions, and the National Bank issued a consistent run of commemorative ECU-denominated pieces throughout the 1980s and early 1990s, partly as advocacy for European monetary integration. Baudouin I, who had reigned since 1951, was a committed Europeanist whose 60th birthday in 1990 provided the occasion rather than the reason.

The bimetallic construction — gold centre, silver ring — was technically demanding for its era and relatively rare in European commemorative issues at the time.