100 Dollars - Elizabeth II 3rd Portrait - Koala - Platinum

The Australian Platinum Koala series launched in 1987, making Perth one of the earliest mints globally to issue a platinum bullion coin in a market then dominated almost entirely by the Palladium Maple and the Platinum American Eagle's absence — the U.S. didn't release its own platinum bullion coin until 1997. The 1997–1998 issues fall under Ian Rank-Broadley's third effigy of Elizabeth II, adopted by Australia that year after the Royal Mint's phased rollout across Commonwealth nations.

Mintages for these one-ounce platinum issues were tightly capped, rarely exceeding a few thousand pieces annually.