Prep supplies, definitely. Gold and silver? Useful for jewelry, not much else. And for them to be accepted as currency, people have to have confidence that they're genuine. How many people today could tell gold from brass?
Exactly. They're commodities - nothing else.
England used to use "tally sticks" (wood) for their currency before the Bank of England was sprung upon them.
The colonies used "colonial script" (paper) until England came after them for it.
It was extremely difficult to explain to people in 2008 why gold and silver would not rise like a meteor, why oil would eventually drop to $30/barrel, and why the US Dollar index would greatly strengthen against a basket of foreign currencies.
“How many people today could tell gold from brass? ”
That one’s pretty easy. It’s mallebility is pretty singular:
Gold—the original bite-coin.