It is quite interesting how so many still believe in the traditions regarding gold and silver. Even the term, "precious metals" indicate this faith, maybe the Faith, in these worthless metals. Historically, the king of Lydia used gold alloy coins, that were readily available in his region, as means of exchange. He convinced his subjects to accept the coins by accepting taxes only with the coins. For whatever reason, the trend was mimicked by other states. Gold has no intrinsic value, as it is functionally useless. Only by sheer intransigence of tradition, do people still hold to these as currency.
All money is "made up." The belief in the system gives value to currency.
I suppose here we see the difference between natural and artificial wealth.
Natural wealth, such as trees, cars, fancy paper, and gold, is valuable because you can do something with it. For example, make shiny jewelry from gold, or drive a car around. Every form of currency aside from digital blips (as you put it) has some physical value, however little.
But artificial wealth, dollars, bonds, contracts, etc, is created sheerly by human whim, and rises or falls in value based on that whim. The government's whim, in the case of money, is absolute, most directly because of taxation.
Wealth is an extension of a man's emotional state, fluctuating with circumstance and desire. Indeed, men are blessed with the resources of this globe, but like the desert nomad who believes two jugs of water more valuable than a lake, we impoverish ourselves via arbitrary quantification and divisions.