The Australian ten-ounce silver piece (abbreviated as 10 oz and designated with Ag for "silver") is a bullion and commemorative coin format used mostly by the Perth Mint, which only makes collector and bullion coins and other bullion products.
The Australian Silver Kookaburra series was introduced in 1990 by the Perth Mint in the silver one-ounce format. Subsequently, the range was expanded in 1991 to also include 2oz silver, 10oz silver and 1 kg silver; much later, gold and platinum formats were also introduced.
The coins in the series have legal tender status in Australia and are one of very few legal tender bullion silver coins to change their design every year, always featuring a kookaburra - a bird native to Australia, which is the largest member of the kingfisher family and the national bird of Australia. This and their limited annual mintage may, unlike for many other bullion coins, raise their numismatic value over the value of silver used.
The 2015 issue is a special anniversary edition marking 25 years since the introduction of the Australian Kookaburra bullion range, and re-creates Stuart Devlin's original design of the 1990 Australian Kookaburra. | 
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