In 1999, to celebrate the 100th Anniversary of the opening of the Perth Mint, the Perth Mint released a Limited Issue Bi-Metal $100 One Hundred Dollar Gold Matte Proof Sovereign Coin.
It features a solid 22ct Gold centerpiece
, with the same specifications as the original Perth Mint Sovereign and is surrounded by a 99.99% pure silver border.
The Perth Mint Centenary Sovereign honours both the historic role of the Sovereign and the importance of silver in the Mint's heritage.