The Australian 50 cent denomination was first introduced as a silver coin with decimalisation on 14 February 1966, but was changed in 1969 to its current specifications: a large dodecagonal (12-sided) copper-nickel coin; apart from the usual design featuring the Australian Coat of Arms, the denomination is also extensively used to issue circulating commemorative coins with various reverses. It is one of the heaviest coins in regular circulation in the world.
Apart from circulating coins, the Royal Australian Mint has a range of Non-Circulating Legal Tender (NCLT) 50 cent coins issued for collectors, such as this one.
This coin was issued as part of the six-coin annual baby sets for 2018 called Possum Magic 2018 Uncirculated/Proof Baby Coin Set and is dedicated to one of Australia’s most celebrated children’s books: Mem Fox’s Possum Magic. Its reverse features an illustration from the book and is coloured in the proof version. The sets also include a colour printed token.
No coins of this type were released into circulation. | 
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