Each Australian lunar series from The Perth Mint is based on the 12 animals in the Chinese zodiac.
In 1996, The Perth Mint started issuing gold coins based on the Chinese Lunar animal. After the success of the gold version, a silver lunar series was introduced in 1999. Due to its success, it is now in its third series.
Each coin celebrates a different Chinese zodiac sign, with each cycle lasting 12 years. Series 2 and 3 are also available as an 'Investment' version, with a slightly different design.
These bullion coins are struck from 999 fine silver and have a face value of 1 AUD.
Full mintage breakdown available here.