Capitalizing on his fans’ paranoia that President Obama will combine various tenants of socialism and fascism to destroy the American economy and render the dollar worthless, Glenn Beck has been urging his followers to buy gold. The most interesting question here is not why Beck is shilling for Goldline International, but how did gold get so valuable in the first place? It’s just metal, you can’t even eat it.NPR’s Jacob Goldstein and David Kestenbaum set out to answer that question with a simple tool: the periodic table of elements. Are there any other chemical elements that could replace gold? Not really. Most of the 180 elements are unusable: they’re gasses, they explode, they’re radioactive, or they’re too common or too rare. Eliminating elements that fall into those categories "leaves us with just five elements: rhodium, palladium, silver, platinum and gold"--precious metals, Goldstein and Kestenbaum write. But silver tarnishes, rhodium and palladium were discovered only in the 1800s, and platinum melts at 3,000 degrees--way too hot for pre-industrial man. The reporters asked their expert, chemical engineer Sanat Kumar: "If we could run the clock back and start history again, could things go a different way, or would gold emerge again as the element of choice?" Kumar explained, "For the earth, with every parameter we have, gold is the sweet spot... It would come out no other way."