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Australian round fifty-cent coin

Fifty cents
Australia
Value 0.50 AUD
Mass 13.28 g
Diameter 31.51 mm
Thickness 2.00 mm
Edge milled
Composition 80% silver, 20% copper
Years of minting 1966
Catalog number
Obverse
1966 Round 50 Cent Coin Obverse.png
Design Queen Elizabeth II, Australia's Queen
Designer Arnold Machin
Design date 1966
Reverse
1966 australian 50 cent piece circular.jpg
Design Coat of Arms of Australia
Designer Stuart Devlin
Design date 1965

The round fifty cent coin was the highest-denomination and largest diameter coin of the Australian dollar's decimal coins, introduced in 1966. Due to large amounts made in 1966 and the rising cost of silver, it was not made in any other year. It was replaced by a dodecagonal 50 cent coin in 1969, which retained its reverse of the Australian Coat of Arms.

It was made of 80% silver and 20% copper, but as the value of a free-floating silver piece grew higher, the coins' bullion value became higher than their face value and so were withdrawn from circulation. A total of 36.45 million coins were minted with 14 million put into circulation.


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