Well, for starters, it's up to the federal government to pull the plug and Assistant Minister for Treasury and Finance Zed Seselja said the government had no plans to do so, as "there is no compelling case" why it should. Facing extinction: The humble 5¢ piece is expected to die "a natural death" within the next five years. Credit:Danielle Smith Ross MacDiarmid, chief executive of the Royal Australian Mint, feels the same way, telling the Herald that he believes the 5¢ piece will "just naturally die" without any need for government intervention. "If you took the trend lines through where we are today, you could probably say within five years you might see that 5¢ pieces are no longer in demand," he said. "The need for 5¢ pieces will just diminish and it will be a gradual decline until they are effectively no longer be required."

Loading Last year, the mint produced 18 million 5¢ pieces. This is 70 per cent less than it was producing in 2012, Mr MacDiarmid said. "Of course the coins that are going to be most impacted by that are going to be the low denominations, 5¢ and 10¢ pieces and I guess progressively working our way up over time it will be the 20¢ piece as well." So, who's still using them? While the decline of 5¢ pieces, and physical currency more broadly, has been predicted for many years, our smallest coin's battle for survival is not quite over yet.

Mr MacDiarmid said that research showed groups such as elderly Australians, students, people from low socio-economic and recent migrant backgrounds still prefer using cash. And as long as someone is using cash and retailers continue to price items to .95 cents, 5¢ pieces will be taking up space in wallets and falling down the back of lounge cushions. And at least one part of the Australian economy would be sad to see the coins go for good: charities. Connie, left, and her brother Samuel Johnson, right, and Connie's sons, Willoughby, 10, and Hamilton, 9, toss coins for their Big Heart Project, to raise money for cancer research. Credit:Karleen Minney Last year, millions of 5¢ coins were donated as part of The Big Heart Project, cancer sufferer Connie Johnson's final public appearance for the Love Your Sister charity before she died of the disease. The project raised more than $2 million for cancer research.

Loading On a smaller scale, charity donation jars in shops and other public spaces rely on people having unwanted coins weighing down their wallets. "We know that 5¢ pieces are still being purchased [from the mint], and we can only assume that people are using them, but most of them are going into charity jars and or charity boxes," Mr MacDiarmid said. Australia is no stranger to giving currency the flick when it no longer earns its keep. In 1990, 1¢ and 2¢ coins were removed from circulation when their bullion value exceeded their face value and rising inflation rendered them obsolete.

However, they are still legal tender. It's likely the "natural death" of 5¢ pieces would look very similar; new coins would no longer be produced, but those already existing in the community could continue to be used as currency. And what about the 10¢ piece? "I think it's on a similar trajectory but at a slower rate, so it may have a longer life," Mr MacDiarmid said.