100 Dollars - Charles III Red Centre

Niue has served as an issuing authority for collectible bullion and numismatic programs since the 1990s, functioning under a licensing arrangement that allows third-party mints — typically the New Zealand Mint — to produce coins bearing its name and legal tender status. The Red Centre series draws on Australia's interior desert ecology, a subject that carries no particular monetary or political history worth excavating.

One troy ounce of .9999 fine gold at this diameter puts it squarely in the standard bullion coin format, and without a documented mintage figure or known production anomaly, the KM reference is the most durable fact here.