The Australian one ounce platinum piece (abbreviated as 1 oz and designated with Pt for "Platinum") is a bullion coin format. Uniquely, in Australia there are two mints authorised to strike legal tender: the Royal Australian Mint (which also makes the country's circulating coinage) and the Perth Mint which only makes collector and bullion coins, as well as other bullion products.
Both mints endeavour to create coins with attractive designs, and to introduce new designs and themes often, in order to raise the numismatic value of the coins over the value of previous metal used.
This coin is part of the long-running Australian Kangaroo bullion coin series by the Perth Mint.
The Mint says about it:
With a tradition dating back to the 1980s, the Australian Kangaroo is a trusted bullion coin series featuring imagery of the iconic animal that takes its name from the Guugu Yimithirr word "gangurru". First Nations people have a relationship with the kangaroo dating back tens of thousands of years. Today, it is recognised internationally as Australia’s definitive animal emblem. | 
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