My guess is Fort Knox gold. U.S. "swapped" gold with Bundesbank and then sold that gold on the open market during the past two years. That way there was no net effect on the U.S. balance sheet (which they refuse to allow to be audited).
Now, I'm betting, the Bundesbank is starting to sell off the swapped gold, which is physically coming from Fort Knox (and the vaults under Republic Nat'l Bank in N.Y). Again, the purpose is to prevent a run on the dollar, and by extension, the Euro.
After all, gold is not priced in dollars, as most Americans think. Instead the dollar is priced in oz. of gold. When gold goes up in price, it is saying that the value of the dollar (and Euro) is going down, that's all.
Get gold. It's the real money and it's not subject to inflation.