2 Pounds - Elizabeth II 65th Ann. Coronation, Gold Proof

Alderney, one of the smaller Channel Island dependencies, has no independent monetary authority of consequence — its commemorative issues are produced under license and struck at the Royal Mint or contracted private mints, with legal tender status that is largely nominal. The 65th coronation anniversary in 2018 had no particular constitutional significance; unlike the 60th or the forthcoming 70th, it attracted no major ceremonial observance in the UK itself.

The 22-carat specification at 16g places this squarely in the half-sovereign weight class without being one.