1966 Australia Silver Fifty Cents XF

Introduction and Composition: Introduced in 1966 as part of Australia's transition to decimal currency, it was the highest-denomination and largest diameter coin at the time. It is made of 80% silver and 20% copper.
Design: The obverse features the second portrait of Queen Elizabeth II, while the reverse depicts the Australian Coat of Arms, supported by a kangaroo and an emu, along with the numeral "50" and the designer's initials "SD" (Stuart Devlin).
Withdrawal from Circulation: Due to rapidly rising silver prices shortly after its introduction, the intrinsic value of the silver content in the coin quickly exceeded its face value, leading to its withdrawal from circulation. It was replaced by a dodecagonal (12-sided) copper-nickel 50 cent coin in 1969.
Collectibility: As the only circulating Australian decimal silver coin and due to its unique history, the 1966 round 50 cent coin is highly sought after by collectors and investors for its historical significance and silver content.