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

Australia's platinum Koala series launched in 1988 as a direct competitor to the Canadian Maple Leaf and American Platinum Eagle programs that were drawing investor capital away from Australian precious metals. The Perth Mint entered the market aggressively, issuing platinum in four denominations simultaneously — a strategy few sovereign mints attempted at the time.

The third portrait of Elizabeth II, sculpted by Raphael Maklouf, was adopted by Australian coinage in 1985.