If you were to stuff all the world's gold in a single room, how large would it have to be? According to Warren Buffett, one that's 67 feet long, 67 feet wide, and 67 feet tall. And he's actually pretty spot on, according to an annual survey conducted by Thomson Reuters GFMS, whose tally is about 377 million pounds—or an amount that would fit into a cube that's 68 feet on each side. But the BBC asks the fascinating questions: "Is that all there is? And if so, how do we know?"
Most agree there's no less than that amount: The BBC finds the low end of estimates is around 342 million pounds; but the high end tops out at a staggering 5.5 billion. The reason for the massive range is the relatively massive number of years gold has been mined—about six millennia—per a gold historian. GFMS asserts that about 28 million pounds had been mined by 1492; but some think that's far too low, and point to King Tut's tomb as proof. His coffin was forged from more than 3,000 pounds, "so imagine the gold that was found in the other tombs that were ransacked before records were taken of them," says one gold expert, who adds that China remains fairly secretive about how much it is unearthing. The BBC is unwilling to deem any estimate correct, noting that because they're based on a series of estimates, "maybe they're all way off." But the figure is likely to grow: The US Geological Survey believes another 114 million pounds of it have yet to be discovered. (Read more gold stories.)