I have to quote Terry Pratchett here:
‘It costs more than a penny to make a penny,’ ■■■■■ murmured. ‘Is it just me, or is that wrong?’
‘But, you see, once you have made it, a penny keeps on being a penny,’ said Mr Bent. ‘That’s the magic of it.’
‘It is?’ said ■■■■■. ‘Look, it’s a copper disc. What do you expect it to become?’
‘In the course of a year, just about everything,’ said Mr Bent smoothly. 'It becomes some
apples, part of a cart, a pair of shoelaces, some hay, an hour’s occupancy of a theatre seat. It may even become a stamp and send a letter, Mr Lipwig. It might be spent three hundred
times and yet — and this is the good part — it is still one penny, ready and willing to be spent again. It is not an apple, which will go bad. Its worth is fixed and stable. It is not consumed.’
Mr Bent’s eyes gleamed dangerously, and one of them twitched. ‘And this is because it is ultimately worth a tiny fraction of the everlasting gold!’
‘But it’s just a lump of metal. If we used apples instead of coins, you could at least eat the apple,’ said ■■■■■.
‘Yes, but you can only eat it once. A penny is, as it were, an everlasting apple.’
‘Which you can’t eat. And you can plant an apple tree.’
‘You can use money to make more money,’ said Bent.
‘Yes, but how do you make more gold? The alchemists can’t, the dwarfs hang on to what they’ve got, the Agateans won’t let us have any. Why not go on the silver standard? They do that in BhangBhangduc.’