The Australian ten ounces silver piece (abbreviated as 10 oz and designated with Ag for "silver") 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.
This ten-ounce silver coin with a face value of $10 is part of the Perth Mint's bullion coin range featuring native animals, and depicts a Mother and baby Koala.
It is the first issue in the The Next Generation series, also known as Mother and Baby, which depicts a mother and baby of an iconic Australian animal, with a different design every year.
The koala family’s evolution in Australia dates back some 30 to 40 million years, when it separated from its closest relative, the Australian wombat. The coin’s reverse depicts a mother koala perched on a branch with its baby on its back. Eucalyptus leaves, radial lines and The Perth Mint’s "P" mint mark are also included in the design.
This 10oz silver bullion coin is issued as a piedfort which has the same diameter as a 5oz silver coin but is double the thickness. | 
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