50 Cents KM#68 15.55 g., Copper-Nickel, 31.65 mm. Ruler: Elizabeth II Obv: Portrait of Queen Elizabeth II to the right, is surrounded with the inscription Rev: Australia coat of arms (the escutcheon is carried by a red kangaroo (Macropus rufus) and an Emu (Dromaius novaehollandiae)) and the numeral "50". Designer's mark "SD" below. Obv. Designer: Arnold Machin Rev. Designer : Stuart Devlin. Shape: Dodecagonal (12-sided) .Edge: Plain