1 Dollar - Elizabeth II 4th Portrait - Millennium

The pad-printing process used here — a technique borrowed from industrial product decoration — was still experimental for numismatic applications at the turn of the millennium, and the Royal Australian Mint was among the first sovereign mints to deploy it on a circulating-format commemorative. Color adhesion on these pieces varies more than the mint publicly acknowledged, and examples with significant ink degradation are not uncommon despite careful storage.