The Australian half ounce silver piece (abbreviated as 1/2 oz and designated with Ag for "silver") is a bullion and commemorative 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.
This half-ounce silver ingot with a face value of $1 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:
"To celebrate 2021, the year of the Metal Ox, the Royal Australian Mint has produced this beautiful 2021 $1 1/2 oz Silver Ingot. Featuring the powerful Ox standing amid willow branches to represent humility, the ingot honours those people born under the sign of the Ox, who are believed to be patient, honest and dependable. A brilliant and auspicious gift or collectible for Chinese New Year 2021."
The coins were issued boxed, in Brilliant Uncirculated grade, Royal Australian Mint Product Code: 10489, issue price: A$70.00. | 
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