Who holds all the United States gold? Federal Reserve or the Treasury?

So if the Fed collapeses what happens to the 6 trillion in debt they currently hold? What happens when private companies go bankrupt? All of the business property and assets are sold and the sales proceeds are used to pay off as many of the business debts as possible. The business then stops all operations and the remaining debts, if any, simply disappear. Poof. Treasuries might lose 5% (reserve holdings). Am I on target?