It is long, but worth sharing:
Several years ago, Walter Luhrman, a metallurgist in southern Ohio, discovered a copper deposit of tantalizing richness. North America’s largest copper mine—a vast open-pit complex in Arizona—usually has to process a ton of ore in order to produce ten pounds of pure copper; Luhrman’s mine, by contrast, yielded the same ten pounds from just thirty or forty pounds of ore. Luhrman operated profitably until mid-December, 2006, when the federal government shut him down.
The copper deposit that Luhrman worked wasn’t in the ground; it was in the storage vaults of Federal Reserve banks, and, indirectly, in the piggy banks, coffee cans, automobile ashtrays, and living-room upholstery of ordinary Americans. A penny minted before 1982 is ninety-five per cent copper—which, at recent prices, is approximately two and a half cents’ worth. Luhrman, who had previously owned a company that refined gold and silver, devised a method of rapidly separating pre-1982 pennies from more recent ones, which are ninety-seven and a half per cent zinc, a less valuable commodity. His new company, Jackson Metals, bought truckloads of pennies from the Federal Reserve, turned the copper ones into ingots, and returned the zinc ones to circulation in cities where pennies were scarce. “Doing that prevented the U.S. Mint from having to make more pennies,” Luhrman told me recently. “Isn’t that neat?” The Mint didn’t think so; it issued a rule prohibiting the melting or exportation of one-cent and five-cent coins. (Nickels, despite their silvery appearance, are seventy-five per cent copper.) Luhrman laid off most of his employees and implemented his corporate Plan B: buying half-dollars from banks and melting the silver ones (denominations greater than five cents aren’t covered by the Mint’s rule); mining Canadian five-cent coins (which were a hundred per cent nickel most years from 1946 to 1981); and lobbying Congress.