The Australian 50 cent denomination is a large dodecagonal (12-sided) copper-nickel circulating coin; apart from the usual design featuring the Australian Coat of Arms (by Stuart Devlin) which has not been changed since its introduction, the denomination is also often used to issue circulating commemorative coins with various reverses. It is one of the heaviest coins in regular circulation in the world.
Apart from the circulating coinage, the Royal Australian Mint has an extensive program issuing 50 cent coins for collectors (Non-Circulating Legal Tender, or NCLT). Most of them share the same specifications with the circulating coins. However, some of them are 14-sided (a Tetra-Decagon) and are not compatible with the circulating coinage. | 
