500 Francs / 75 Ecus Big Ben

The 75 Ecus denomination places this squarely within France's brief experiment with ECU-denominated coinage, a series launched in anticipation of European monetary union that quietly died when the euro arrived and the franc was pensioned off. Paris issued these dual-denomination pieces across several years in the early 1990s, each pairing a French franc value with an ECU equivalent tied to the then-current exchange rate — a politically loaded gesture toward European integration that not everyone in the Assemblée nationale was enthusiastic about.

The Big Ben issue was part of a broader Franco-British commemorative program tied to the Channel Tunnel, which opened in May 1994 after years of delays and cost overruns that nearly bankrupted Eurotunnel before the first passenger ever boarded.