In 1872, prospectors Philip Arnold and John Slack arrived in San Francisco with a bag full of rough diamonds, rubies, and emeralds, claiming they found a remote mesa overflowing with precious gems. Bank president William Ralston jumped at the opportunity to finance their discovery and gathered a syndicate of wealthy investors, including Charles Tiffany and Baron Ferdinand de Rothschild. To verify the claim, Tiffany examined the gems, and top mining engineer Henry Janin was dispatched to inspect the secret site on a remote mesa in Wyoming.
Unbeknownst to the experts, Arnold and Slack had secretly purchased industrial-grade uncut diamonds in London and Amsterdam and sprinkled them across the desert landscape. Janin enthusiastically endorsed the field as a multi-million-dollar discovery. The trick worked until geologist Clarence King visited the mesa and noticed that diamonds and rubies—gems that never naturally co-occur—were found in identical proportions, leading him to discover anthills stuffed with cut diamonds.