Hi faul,
Yep. Looks like gold was a thing for primitive peoples as I mentioned. But unfortunately, it is a lousy form of currency. Have you ever thought about debasement of coinage? It's as long as the history of gold as a currency, more-or-less.
Re fiat currencies: the oldest modern fiat currency is the US dollar. Looks like it's going strong. There is no gold standard and if I remember correctly, most countries abandoned the promise to pay a person in metal long since. Why bother to tie yourself to a shiny object when there's a whole economy to support the value of a currency.
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