1 Dollar - Elizabeth II Lucky Shamrock Piggy

Niue has operated as a prolific licensing hub for novelty bullion since the early 2000s, contracting private mints to produce collector pieces that use its sovereign issuing authority while bearing no relationship to the island's domestic economy. This piggy bank shaped piece — one of a series of small-format silver novelties — falls squarely in that category.

At 2.6 g, the silver content is minimal by bullion standards, placing the collector premium well above any intrinsic metal value.