In 2000, a number of spectacular error coins stunned the numismatic world
. One such error was a coin with the front of a 50 State Quarter and the back of a Sacagawea dollar. This was the first U.S. coin ever to bear two denominations. Because the two dies differ in diameter, no one believed it was even possible for such an error to exist; in fact, some professionals believe these error coins were made deliberately. The error received tremendous publicity in the national media, causing millions of non-collectors to begin examining their change. You can bet that many of them have become coin collectors.