Coins of the Australian dollar

Coins of the Australian dollar were introduced on 14 February 1966, although they did not at that time include one-dollar or two-dollar coins. The dollar was equivalent in value to 10 shillings in the former currency (half of a pound).

Produced by the Royal Australian Mint, all current coins portray Her Majesty Elizabeth II, Queen of Australia, on the obverse, with the present effigy having been designed by Ian Rank-Broadley. This is matched with designs by the Australian-born artist Stuart Devlin on the reverse. They now comprise 50c, 20c, 10c and 5c coins – all still referred to as 'silver' though actually 75% copper and 25% nickel, and for many years there were also "bronze" 2c and 1c coins.

The 50c coin originally had a circular shape, and contained 80% silver and 20% copper, so that the material of the coin was worth more than 50c. It was made to almost identical dimensional specifications as the British 2'6 pence half crown. However, to avoid confusion among the round coins, and because of its excess value, it was only produced for one year then withdrawn from circulation; there were no 50 cent coins minted for 1967 or 1968. It was changed to a 12-sided shape for 1969 and all following years, but the 12 sided issue was minted as a specimen piece in 1966-67 to test the design. It has since been issued in both standard and commemorative designs.

The standard designs on both versions of the coin are the same: the obverse carries the effigy of the sovereign, and the reverse shows the Coat of Arms of Australia. The dodecagonal version has a mass of 15.55 g and a diameter of 31.5 mm, and the round silver version has a mass of 13.28 g and diameter of 31.5 mm. 94.13 Australian 1966 round 50c coins make up a fine kilogram of silver.

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