Charles Martin Hall and the Discovery of Aluminum

Before Charles Martin Hall, aluminum was rarer than silver. The metal existed in abundance inside ordinary clay and rock, but no one could pull it out cheaply enough to matter. It was priced like a precious metal.

Hall was twenty-two years old, a recent graduate of Oberlin College, when he cracked the problem in eighteen eighty-six. Working in a woodshed behind his family's house, he discovered that dissolving aluminum oxide in a molten mineral called cryolite and passing an electric current through it would deposit pure aluminum at the bottom. The same discovery was made independently that same year by a Frenchman named Paul Heroult, born the same year as Hall and dead the same year too.

Hall's process made aluminum cheap. Within a generation it was everywhere: cookware, aircraft, the infrastructure of modern life. He co-founded what became Alcoa and left the bulk of his fortune to Oberlin. The metal that once adorned the cap of the Washington Monument as a luxury material became the skin of the twentieth century.