Even a short time ago, people just couldn't get enough of the factory's output but now virtually nobody wants to touch it.

We are talking, of course, about the Royal Australian Mint. It is a commercial operation but demand has dropped, well, like a coin through a grill in the road.

It hasn't sold any coins to banks since February. Easter is normally a big time when the banks take coins from the Mint but this year: zilch.

The other big time when the banks want more coins is the end of the year.

"We are nervously waiting on what it might look like for the pre-Christmas period," the mint's chief executive, Ross MacDiarmid, said.

"It could well be that there is no demand for that period. The other concern is what post-COVID looks like".

The Royal Australian Mint has a monopoly on producing "legal tender" coinage with the Queen's head embossed on it.

There is a mint in Perth but its output doesn't go into circulation, just to collectors and investors in gold. And "paper" money which is actually made of plastic is manufactured in Melbourne.

The real deal Canberra operation sells coins to the banks and sends the profits to the Treasury. (Don't ask how the banks can buy money - only Nobel prize-winners in economics understand).

The Royal Australian Mint employs 253 people, with 13 presses churning out the nation's coinage, minting the money we used to rattle around our pockets and lose behind the sofa.

Until the "Thing" arrived.

Before the coronavirus got among us, 68 per cent of Australians were habitual users of cards for payment.

Now, card use has gone up to 78 per cent of us, with only one in five sticking to coins.

Last financial year, the Royal Australian Mint sent $35 million to the Treasury as profit - the sum is known as "seigniorage", an ancient French term.

This year, that profit for the government has dropped to $30 million - and that's even though the COVID-induced drop in the use of cash has only been for the last four months.

The chief executive is not spelling out what he is going to do as demand for his product falls. "I'm being cryptic but we have plans," he said.

There is a ruse available: Australia is one of the few countries in the world which has coins in two colours.

People have a tendency to keep hold of them. "People take them out of circulation," Mr MacDiarmid said.

This reluctance to spend them means that minting more two-coloured coins would increase demand - and so revenue to the mint and the Treasury.

He has another way of keeping the money flowing in as the demand for cash drops.

The mint makes commemorative medals and special coins in gold (coins have the Queen's head on them; medals don't).

A special edition of a $10 coin made of gold would have a value just in terms of the gold of about $3000.

But commemorative coins are also big business. It's issued series depicting the Chinese Year of the Rat.

The mint offers the $100 coin in the series for $2995.

The 50 cent coin goes for $12.50. The Qantas centenary, the red kangaroo and the anniversary of the end of the Second World War were also money-spinners.

The mint is looking to expand these commercial operations to try to offset the fall in the demand for plain old coins.

Oddly, a recession might also help. In hard times, people cling more to cash.

The big users of cash are the old and the young. In fearful, non-plague times, its use usually spreads because people feel it gives more control of spending. Trust in "real" money vies with fear of what it carries.