The Australian one-ounce gold piece (abbreviated as 1 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:
Depicting a beautifully detailed bird of paradise performing its iconic mating dance, this coin is a magnificent keepsake for bird lovers of any age.
The aptly named birds of paradise are native to northeastern Australia and Papua New Guinea. Known for their dramatic, brightly coloured plumage displayed as part of a flamboyant courtship ritual, they have some of the most magnificent mating spectacles in the bird kingdom.
This proof coin has the design of the previous year's coin, while the bullion Bird of Paradise issue for 2019 has a new design. | 
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