He also revealed that he's not above being duped by fakes. Harrison told Leno that he once paid $11,000 for a letter that was said to have been written by Napoleon Bonaparte.
It turned out that the letter was a forgery. "Every once in a while it happens," he shrugged. "It's a business with risk and reward."
Catch Rick in action on "Pawn Stars," Mondays at 10 p.m. ET on History. "The Tonight Show" airs weeknights at 11:35 p.m. ET on NBC.
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