It seems if some Australians had their way 50 years ago, the nation's change to decimal currency could have seen us trading in dingoes, merinos, kelpies or even dinkums.

Sunday marks the 50th anniversary of Australia's switch-over from pounds, shillings and pence to dollars and cents, on February 14, 1966 – Conversion Day or "C Day".

Canberra author Peter Rees, whose history of coins and tokens in Australia was launched at the Royal Australian Mint on Thursday, said a national competition was held at the time to name the new currency.

"Suggestions from the public included the quid, the dinkum, the digger, the roo, the kelpie, and the emu. There was even a suggestion they call it the merino," he said, with a laugh.

Mr Rees said then Prime Minister Robert Menzies wanted the new currency to be known as the Royal but the public wasn't having it.

"There was a huge backlash," Mr Rees said. "Opinion polls were showing 95 per cent rejection of the name across Australia. Government MPs were inundated with complaints."

Harold Holt, who was treasurer in the lead-up to the change, successfully argued for the Royal to be dropped and replaced with the dollar.

But even he dabbled in a little whimsy, Rees saying Holt fleetingly suggested the currency be called The Austral but feared it would end up being known as The Nostril, given Australians' predilection for rhyming nicknames.

Dollars and cents won out in the end.

"The dollar was a denomination that really had been in existence with various countries over the past two or three hundred years," Mr Rees said.

Governor-General Sir Peter Cosgrove launched Mr Rees' book, Inside the Vault: The history and art of Australian coinage, saying it bought the nation's coins "to life".

General Cosgrove said the new currency also reflected a shift in how Australians saw themselves, as confident and optimistic, with unique designs by Stuart Devlin.

"The new coins were ours. They were designed here. And they were minted in this very building," he said.

Also at Thursday's launch was retired Treasury official, 95-year-old Neil Davey, of Torrens, one of the architects of the decimal system, who came to be known as Mr Decimal.

Mr Davey's PhD thesis, The Decimal Coinage Controversy in the United Kingdom, written in the 1950s, was one of the triggers for the big change in the Australian monetary system.

Five decades later, Mr Davey said he felt a little overwhelmed by all the attention.

"I feel pleased it all went through as well as it did," he said, on Thursday.

Mr Rees, by chance, started work as a copyboy in the week of the changeover, and still had one of the brand-new dollar notes he received in his first pay packet.

He said most people coped well with the switch after a huge education campaign which included the animated character Dollar Bill who sang a jingle about the changeover to the tune of Click Go the Shears.

Royal Australian Mint chief executive officer Ross MacDiarmid earned warm applause at Thursday's launch when he sang a couple of lines from the jingle:

In come the dollars and in come the cents

To replace the pound and the shillings and the pence

Be prepared folks when the coins begin to mix

On the 14th of February 1966

The Mint is celebrating the anniversary by releasing an entire suite of Australia's circulating coins featuring designs from the pre-decimal coins from the half penny to the florin. First to be released by the banks will be the 50 cent coin in its original 1966 circular shape.

The Reserve Bank is also releasing an updated $5 note featuring a new wattle design, fresh security features and a tactile feature to help the vision impaired distinguish between notes.

And the Royal Australian Mint is having an open day on Saturday to celebrate the milestone.

Mr Rees' book is available from the Mint's eShop.