The Australian 50 cent denomination was first introduced as a silver coin with decimalisation on 14 February 1966, but was changed in 1969 to its current specifications: a large dodecagonal (12-sided) copper-nickel coin; apart from the usual design featuring the Australian Coat of Arms, the denomination is also extensively used to issue circulating commemorative coins with various reverses. It is one of the heaviest coins in regular circulation in the world.
Apart from circulating coins, the Royal Australian Mint has a range of Non-Circulating Legal Tender (NCLT) 50 cent coins issued for collectors, such as this one.
In 2010, the Royal Australian Mint produced - apart from the regular brilliant uncirculated, proof and silver proof coin sets - a commemorative gold coin set, the 2010 Gold Proof Set - Australian Numismatic Centenary. Unlike the other sets - which feature the regular effigy of the Queen by Ian Rank-Broadley, which was in circulation in Australia at the time - the coins in the gold set have her effigy by Vladimir Gottwald.
It is a uniquely Australian effigy, designed exclusively for the Royal Australian Mint, by its world renowned designer - Vladimir Gottwald. Acting on a worldwide invitation from Buckingham Palace in 1999, to design a more modern effigy of Queen Elizabeth II, Vladimir Gottwald’s design was eventually selected to honour Her Majesty’s royal visit of 2000 on a commemorative 50c coin.
The 6-coin set contains 5 cents, 10 cents, 20 cents, 50 cents, $1 and $2 coins - all with the Queen's portrait by Vladimir Gottwald.
The coins are made of 99.99% gold. No coins of this type were released into circulation. | 
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