1958 Belgium 20 Francs

This 1958 Belgian 20 Francs coin depicts the Atomium, that 102-meter tall steel structure built for the Brussels World's Fair, capturing the era's atomic-age optimism in a design that still looks like a molecular model gone architectural.

On the obverse, you'll find the Belgian coat of arms, while the reverse shows the Atomium alongside the denomination. It was struck in silver, as was common for commemoratives of the time, though exact composition details vary by source. The coin marked Expo 58, an event that drew millions and showcased postwar Europe's recovery, but don't expect it to tell you much about the fair's infamous traffic jams.

Mintage figures? Lost to time, probably filed away in some dusty archive. As for myths, I've heard tales of these coins being hoarded by fairgoers, but most just circulated like any other franc.

Some collectors prize the uncirculated versions for their mirror-like fields, but that's as far as the excitement goes.