Eighty feet below the streets of lower Manhattan, a Federal Reserve vault protected by armed guards contains about 6,200 tons of gold. 
 
 Or doesn’t. 
 
 The Fed tells visitors its basement vault holds the world’s biggest official gold stash and values it at $240 billion to $260 billion. 
 
 ... ||||| Federal Reserve Chair Janet Yellen traded sharp words in a rare, feisty exchange with a congressman over legislation that could limit the central bank's independence. 
 
 The normally reserved Yellen pushed back against pointed questions from Bill Posey, a Florida Republican. He asked why she's opposed to a bill that would allow the Government Accountability Office, a unit of Congress, to audit the Fed, and, more controversially, review its decisions on interest rates. 
 
 Posey said the bill, known as Audit the Fed, would provide more transparency for the central bank and its decisions. Fed leaders say it would ruin the central bank's credibility by eliminating its independence. 
 
 In January 2017 a version of the Audit the Fed bill was introduced in both chambers. It passed out of committees in both the House and the Senate, but neither version has received a full vote in either the House or the Senate. Few think it will pass the Senate. 
 
 Related: Fed Chief: Trump policies are a "source of uncertainty" 
 
 "For the life of me, I can't understand what the Fed fears. Can you give me an example that would justify the lack of transparency?" Posey asked at a hearing of the House Financial Services Committee. 
 
 "We don't have a lack of transparency," Yellen quickly replied. 
 
 "You do if you can't audit it -- that's a lack of transparency," Posey shot back. 
 
 Fed leaders do make their decisions behind closed doors. But the central bank is audited twice a year -- once by the government through the Fed's inspector general and once by a private auditor. Critics of the bill question the point of a third audit. 
 
 Right now, GAO officials don't attend Fed meetings and are unable to second-guess its decisions. Yellen argues that the proposed law would give them that power. 
 
 Related: Fed raises rates in June 
 
 Posey pressed on. 
 
 "What do you fear about the audit? Can you give me a real-time example?" he said. 
 
 Yellen replied that central bank leaders need privacy to discuss monetary policy without being second-guessed in real time by officials representing lawmakers. 
 
 Posey wasn't satisfied. "Just give me an example -- give me an example -- of how transparency could hurt the Fed? Just give me one example," he asked, holding up his index finger. 
 
 Yellen started: "Because what you're talking about with the GAO are policy reviews ..." 
 
 Posey cut her off. "No, just give me an example." 
 
 She did: "I would envision a situation where the GAO, at the request of members of Congress, might come in and say at our meeting a week ago ... they believe the decision we made was the wrong one at that particular meeting, and I would say that's an extreme interference" into monetary policy. 
 
 Posey replied: "So you're telling me we shouldn't be transparent for the fear of being second-guessed or somebody criticizing you because they thought you were wrong?" 
 
 "What we're talking about is political interference in decision-making by the [Fed's] committee," Yellen said. 
 
 "I don't see that," Posey said. 
 
 "I do," Yellen shot back. 
 
 "Well, give me an example," Posey asked again. 
 
 "I gave you an example," Yellen said, sharply. 
 
 Posey ran out of time, and the hearing moved on. 
 
 Yellen's testimony before the House on Wednesday may have been her last. Her term ends in February, and it's unclear whether President Trump will reappoint her. House leaders repeatedly asked Yellen whether she wants to say on, and she declined to comment.
– The New York headquarters of the Federal Reserve is either home to 6,200 tons of gold, a bunch of fake gold bars, or next to no gold, depending on whom you ask. The Fed has long claimed its vaults hold the world's largest gold stockpile worth as much as $260 billion. But some "wonder if the bank is hiding something about what it's hiding," in the words of the Wall Street Journal. As one precious-metals analyst explains, the Fed has "never in its history provided any proof" of its gold stores beneath lower Manhattan. Visitors see only a sample of bars—which some suspect could be gold-plated tungsten of an equal weight—and only auditors and account holders are allowed to review records; the last audit of Fed gold, involving 367 samples, was in 2012. Raising further suspicions are recent gold prices. Based on those, one investment strategist claims "there has to have been a central bank spewing their gold into the market." Some gold investors believe the Fed could be secretly lending out its gold to keep prices down, though a Fed spokesperson says it doesn't own any of the gold in its headquarters—most is owned by foreign governments—and "does not use it in any way for any purposes including loaning or leasing it out." Outsiders may not get any more clarity unless the "Audit the Fed" bill is passed. Introduced by Sen. Rand Paul, it would allow the Government Accountability Office to audit the Fed and review its decisions on interest rates, reports CNNMoney. Don't hold your breath: It has yet to face a full vote in the House or Senate.