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

Australia's platinum Koala series launched in 1987, making Perth one of the earliest mints globally to issue platinum bullion coins for the investment market. The 1/4 oz denomination attracted particular interest from Japanese buyers throughout the early 1990s, a market that collapsed sharply after the Nikkei's prolonged post-bubble decline gutted discretionary bullion demand. Mintages for these mid-series years reflect that contraction directly.