Q: What world currencies are actually backed by gold?
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.
You are asking the wrong question. Gold didn't back money, gold was the money. And when people started to warehouse it in bank vaults they got receipt which they started trading as if it was gold itself. Later governments through laws and enforcement through force established a monopoly on these paper receipts, gave them names and proclaimed how much weight is represented with a certain number. For instance in the beginning of the 19th century $20 was redeemable for 1oz of gold.
So the phrase "backed by gold" was miss-used ever since the governments grabbed the monopoly on money. The last country where this happened was the USA in 1913 when the FED was created. Before the FED dollars were basically although government issued receipts for gold. But with the FED it soon changed to legal tender which it is today.
Basically the important point to take away from post is that gold is money. And that paper money was just suppose to have made it's trade easier. So when you're looking at BitCoins you cannot have it "backed by gold" because they are two different commodities and the most that you can have is open free trade between the two. Eventually I suspect will get to a very stable and constant price of gold in BitCoins and vice versa.