The Australian Shilling is a silver coin which was used in the Commonwealth of Australia prior to decimalisation. It has the same dimensions and composition as the British pre-decimal shilling, from which it is derived (for a time, the coins circulated in parallel and were interchangeable in Australia - but not in the United Kingdom). A shilling is equal to 1/20th of a pound, or 12 pence.
The reverse of the first type of Australian shilling coins featured the 1908 Coat of Arms. In 1938, this new design superseded it - featuring a merino ram's head; the old type of coins remained in circulation.
Coins issued in 1937 were withdrawn at decimalisation in 1966 after 29 years in circulation, but have never been formally demonetised and are still legal tender as 10 cents.
The 1937 Shilling coin was a pattern which was never released. The existing coins are all uniface. It is thought that - if they had the effigy and legend of Edward VIII - those were then machined off to leave the obverse blank.
According to The Australian Coin Chart 1966 "A few Pattern Shillings dated 1919 and 1937 have been reported and would realise over £500 at Auction".
According to the Catalogue of British Commonwealth Coins 1649 - 1971, "10 to 15 are known". | 
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