The Australian five ounces gold piece (abbreviated as 5 oz and designated with Au for "gold") 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.
The mint says about this coin:
Inspired by the natural beauty of the Kimberley, this 5oz 99.99% pure gold coin depicts the region's landscape at sunrise with a glistening fine white diamond from the Diavik Diamond Mine in Canada.
Dawn is often characterised by a magnificent sunrise which illuminates the sky with magical hues of radiant gold, bright orange, and smoky purple. As fiery light gradually reveals the landscape, the region’s unmistakable bottle-shaped boab trees with their tangle of twisted branches gradually take on solid form. To witness these beautiful trees backlit by an awe-inspiring sunrise is to experience the unique essence of the East Kimberley in Western Australia’s far north. | 
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