That's true but I'm very skeptical that a notable portion of the worth of a currency rests on that. Like I said in another comment, I think there have been plen

That's true but I'm very skeptical that a notable portion of the worth of a currency rests on that. Like I said in another comment, I think there have been plenty of "commodity currencies" (salt, shells, gold) that have attained value as currencies in spite of lacking these things.