Australia has two mints, the Royal Australian Mint (which also makes the country's circulating coinage) and the Perth Mint, which are both very active in the bullion coinage space; coins issued by them are legal tender.
Additionally, there are private issuers of bullion which is not legal tender and is targeted at investors and not at coin collectors - such as this one.
The mint says about this product:
Two Western Australian icons - Argyle Pink Diamonds and The Perth Mint - unite to present this exclusive creation. The Gouldian Finch is an extremely rare and brilliantly coloured bird found in the Kimberley region of Western Australia, the birthplace of Argyle Pink Diamonds. The vibrant colours of their feathers are reminiscent of Argyle’s extraordinary pink diamonds, which exhibit intensity and saturation of colour unlike anything the world has ever seen.
Struck from 1oz of stunning 99.95% pure platinum, this ingot has been superbly crafted by The Perth Mint. A selection of seven fancy intense to vivid Argyle pink diamonds are superbly hand set in an exquisite platinum ingot, crafted by The Perth Mint. | 
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