A question about the meaning of the letter ‘P’ on our coins recently appeared on a popular discussion forum (read the relevant Silver Stackers post here).
Many people are aware that a ‘P’ is our most famous mintmark. (There have been others, but that’s a story for another day!)
The practice dates back to the nineteenth century. Branches of the Royal Mint in Sydney and Melbourne used the letters ‘S’ and ‘M’ respectively to distinguish their gold sovereigns from London-made coins. So when the Perth branch opened in 1899, the sovereign dies supplied from Britain showed a small ‘P’ under Pistrucci’s famous St George and the Dragon reverse.
This custom was revived in 1986 when the initial proof Australian Nugget became the first Australian coin to bear our traditional mintmark.
From that time onward, the ‘P’ was used on other collectable issues, with a modified ‘P100’ appearing on some coins issued in 1999 – the Mint’s centenary.