The one dollar coin circulating denomination (written as $1) was introduced in Australia in 1984, replacing the earlier banknotes. The original reverse design by Stuart Devlin featuring five kangaroos - known in Australia as the "Mob of Roos" design - has not been changed since its introduction.
The denomination is also used by both the Royal Australian Mint and the Perth Mint to issue an extensive range of collector coins, which are legal tender in Australia - such as this one.
This coin was issued as part of the 1999 Masterpieces in Silver - Coins of the 20th Century: Memories six-coin set, highlighting important times in Australian history (mintage limit 15,000, issue price A$125.00). The reverses of each coin show a historic Australian coin design, in mirror-finish proof; the denomination and value are on the obverse.
The five cents coin depicts a 1939 kangaroo-type halfpenny.
The ten cents coin depicts a 1930 penny.
The twenty cents coin depicts a 1942 threepence.
The fifty cents coin depicts a 1918 sixpence.
The one dollar shows a 1940 shilling.
Involved in World War II, Australia’s labour force in 1940 was drained. With no manpower to mine silver this would become the lowest production run since the Great Depression. This shilling’s special place in history was also marked in 1991, when the Royal Australian Mint reproduced its design as a circulating commemorative 50 cent piece - the only circulating coin design to span pre-decimal to decimal coinage.
The two dollar coin shows a 1920 sovereign.
These coins are Non-Circulating Legal Tender (collector issue); composition: fine silver (99.9%). No coins of this type have been released into circulation. | 
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