1909 5 Dollars "Indian Head"

In 1908 the U.S. Mint did something it had never done before and never did again on a circulating coin: it sank the design *into* the gold. No rim, no relief rising off the surface — just a sunken Indian and a sunken eagle, level with the field around them. People weren't sure they liked it. A century later, it's one of the most distinctive coins America ever made.