100 Dollars - Charles III 1st portrait - Australian Kookaburra - Gold Proof High Relief

The Australian Kookaburra bullion series launched in 1990 as a silver program, with gold variants introduced later as high-relief proof issues aimed squarely at the collector market rather than circulation. The Perth Mint's high-relief gold proofs require multiple strikes under substantially greater pressure than standard issues, with dies dressed between each strike — a process that limits die life and keeps mintages deliberately constrained.

This is among the first Perth Mint releases to carry the Ian Rank-Broadley replacement portrait of Charles III approved for Australian coinage, itself a point of transition interest for date collectors working the series.