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 Salt Water Crocodile.
It is part of 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.
Australian saltwater crocodiles are one of the biggest and fiercest predators in the world, with a bite that exerts the greatest pressure measured in any living animal. Despite this, the reptiles are remarkably gentle with their young. After taking her newly born offspring to water in her mouth, the mother often carries her young on her back while submerged - a touching scene that is portrayed on the reverse of this Australian legal tender coin.
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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