In 1966 Australia changed from the pre-decimal system to the decimal system, which obviously necessitated the production of hundreds of millions of shiny new decimal coins. What is less obvious, and not often thought about is whatever happened to millions and millions of circulated pre-decimal coins when Australia said good-bye to them in 1966? Where did those dull worn shillings go and how did they become bright shiny 10 cent coins after C-Day? Instead of finding silver florins in change the public found lustrous platypus 20 cent pieces with a new portrait of the Queen. Where did they go, the bronze halfpennies and pennies, the silver threepences, sixpences, shillings and florins?
It was the job of the Reserve Bank to withdraw pre-decimal coins from circulation but then it was up to the Royal Australian Mint to handle disposal of the coins. The halfpenny and penny were easy because the alloy was the same as that needed to produce one and two cent pieces. Later the bronze was also used in the production of overseas coins. The old coins were purchased by the Royal Australian Mint from the Reserve Bank at face value and turned into the new bronze 1 cent and 2 cent coins. Because of the sheer quantity of coins needed for the changeover it was also required to purchase coin blanks and raw metals to manufacture the 1 and 2 cent coins. Some bronze pre-decimal coins were added to the copper-nickel melt to help provide the copper content for the manufacture of the 5 cent, 10 cent and 20 cent. Care had to be taken in regulating the alloy composition during this process.
Pre-decimal coins in larger denominations contained silver, post 1946 coins were 50% silver and pre-1946 92.5% silver. Most coins in circulation around that time were “post” silver (post 1946) and contained 50% silver. The florins, shillings and sixpences were collected and sold to overseas companies (by tender) for refining at the prevailing world metal prices. Successful tenderers were Johnson Matthey (Bankers) Ltd, London and Deutsche Gold-Und Silber-Scheideanstalt Vormals Roessler, Frankfurt. The Perth Branch of the Royal Mint was tasked to refine withdrawn threepences. As payment the Perth branch of the Royal Mint kept the refined copper and returned the refined silver to Treasury. As of June 30th 1968 the Perth branch of the Royal Mint had refined $5 million worth of threepences producing around 4 million ounces of fine silver.
The penny, halfpenny and threepence were very quickly removed from circulation during the changeover so the Mint could build up a stockpile of one and two cent pieces that were distributed quickly to help ensure a smooth transition. Over the following two years the silver sixpences, shillings and florins were phased out after a dual currency period. A Proclamation fixed an enforceable date of August 1st 1967 as the date for all legal documents to be expressed in dollars and cents. The decimal system was the sole legal currency in Australia from that date. However, trading with the old money continued to occur after this date as the old coins continued to surface and be spent. In December 1969 the Mint had ceased bulk sorting of coins to remove pre-decimal currency as it had become unprofitable and the Decimal Currency Board submitted it’s final report and wound up on June 3rd 1969.
Today you can still find the odd pre-decimal coin in bulk lots of decimal coins or your change. Even the first 50 cent piece which was round is still spent on occasion for 50c despite it being widely (but not widely enough apparently) that the silver value far exceeds face value. Many old coins were kept as mementos of the old time and a lot of coins have been kept by collectors.