1848, American History Museum
The tiny piece of metal that fueled a massive population shift
Building a sawmill for John Sutter in Coloma, California, in 1848, James Marshall spotted something glittering in the American River. He picked up a small flake of metal and bit it to confirm his hunch: It was gold. The piece was sent to President James Polk, who told Congress that gold had been discovered in California. Nearly half a million people surged into what would become known as the Golden State, madly digging up as much as 12 million ounces of gold within five years and igniting the settlement of the West.