Commemorate a landmark milestone in Australian numismatics with the 2006 Eight Coin Proof Set – 40 Years of Decimal Currency, a special Royal Australian Mint annual issue celebrating four decades since the introduction of dollars and cents on 14 February 1966.

For this significant anniversary, the standard six-coin proof set was expanded to eight denominations, uniquely including the long-withdrawn 1c, 2c, and the iconic round 50c – a faithful recreation of the original 1966 design dated 2006. The round 50c, originally struck in 80% silver, was quickly phased out after 1966 due to rising silver values, making this proof version a rare modern tribute. The 1c and 2c coins, later removed from circulation due to production costs and low purchasing power, complete this nostalgic lineup alongside the current 5c, 10c, 20c, 50c (dodecagonal), and $1, $2 coins.

This expanded 2006 proof set remains one of the most popular and sought-after annual issues, offering collectors a unique opportunity to own the "missing" denominations in pristine proof quality.