2016 Australia's First Mints One Dollar Fine Silver Proof Coin. The discovery of gold within Australian soil led to a time of intense growth during the 19th century. This valuable metal was sourced from Australian earth and converted to unofficial currency at the Adelaide Assay office and official currency at Royal Mint branches established in Sydney, Melbourne and Perth. As the producer if Australian circulating coins since 1965, the Royal Australian Mint celebrates history with this mintmarked coin. This coin is reminiscent of a Sydney Mint sovereign, the only sovereign design unique to Australia. Mintage limited to 5000. Coin comes with certificate of authenticity. Please contact Adelaide Exchange Jewellers to find out more on this item.