The Australian 50 cent denomination is a large dodecagonal (12-sided) copper-nickel circulating coin; apart from the usual design featuring the Australian Coat of Arms (by Stuart Devlin) which has not been changed since its introduction, the denomination is also often used to issue circulating commemorative coins with various reverses. It is one of the heaviest coins in regular circulation in the world.
Apart from the circulating coinage, the Royal Australian Mint has an extensive program issuing 50 cent coins for collectors (Non-Circulating Legal Tender, or NCLT). Most of them share the same specifications with the circulating coins. However, some of them are 14-sided (a Tetra-Decagon) and are not compatible with the circulating coinage.
This coin was issued as part of the Lunar Series of coins to mark the Chinese Year of the Ox (12 February 2021 - 31 January 2022).
The Mint says:
"The Royal Australian Mint wishes good fortune, hope and prosperity to all in 2021, the Lunar Year of the Ox. This tetra-decagon shaped coin honours the strong, open-minded and patient people who are born under the sign of the Ox, the second sign of Sheng Xiao, the Chinese Zodiac. This coin will be a valued collectible or a traditional gift for those who enjoy coins or celebrate Chinese New Year."
The coins were only issued carded, in Brilliant Uncirculated grade, Royal Australian Mint Product Code: 10487, issue price: A$12.50. They were released on 22 January 2021.
No coins of this type were released into circulation. | 
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