The dodecagonal type I fifty cent was issued to replace the round 1966 fifty cent from 1969 to 1984 with a number of
dated 1966 and 1967. It is struck on a dodecagonal
planchetwith the Arnold Machin portrait of HM Queen Elizabeth II on the obverse, and Stuart Devlin's interpretation of the Australian coat of arms on the reverse. Devlin's initials (SD) can be found on the bottom of the reverse underneath the denomination. The type was struck exclusively at the Royal Australian mint in Canberra.