If precious metals were the currency then would it even be possible for the economy to go so wrong? I suspect that precious metals will always rise back to the top even in the bad times as bartering doesn't seem like a long-term solution as a barter-based economy is inefficient. I'm reminded that there was a Star Trek DS9 episode about this ("In the Cards"), where the two kids spend an entire episode bartering goods to acquire something that they could've gotten in five minutes if they'd used currency. If a crisis happens and we use something that is in high demand but not [permanently] scarce, like bullets, as currency then eventually more people will work to make bullets and then bullets will lose their scarcity and inflation will devalue the bullet currency. At that point we'd switch back to gold/silver since, while medieval alchemists and 1950s scifi writers thought that we would be creating more gold and silver by now, AFAIK it hasn't happened yet.