http://answers.yahoo.com/question/index?qid=20080827115251AAYDgdWQ: What world currencies are actually backed by gold?
A: None
Im no economist, but what would it take for bitcoins to be "backed by gold"?
Possible, Plausible or Impossible?
I see two possibilities either a wealthy person puts up some gold to back the whole currency, or a bitcoin wallet provider purchases gold and its customers wallets are backed by the gold standard.
P.S. I have no gold. Just thinking out loud.
It is plausible but impossible in practice
Theoretically, you could back up a cryptocurrency with physical gold, and I know that some coins are in fact claiming just that (though I don't know how true their claims are). It is definitely not possible to back up Bitcoin with gold since there is no single entity which controls it. Otherwise, you would just be selling gold for bitcoins and vice versa at a certain price, fixed of floating, as this is what your idea (actually, two ideas) comes down to. Needless to say that it would have little to do with real backup by gold or any other hard asset. You should have complete control over the token which you are going to redeem for gold, including the clause where you have the right to revoke certain tokens or declare them illegal at your own discretion