When fancy jewelers loan their diamonds to celebrities for big events, they often send a security guard along too, just in case. (You know, something might get stolen, or the celebrity wearer could get drunk, or a piece of jewelry might just fall off and get lost in the shuffle of cheek-kisses and red-carpet posing.) But apparently Chanel Iman doesn't bother with those security precautions, no matter what she's wearing, because she can protect herself. "I don’t worry about that too much, because I’ve taken boxing," she explained at last night's exhibition preview party for "New York City in the '70s," hosted by Cartier and Aldo Cipullo. "I can definitely knock somebody out," she continued, "but you don't want to see that. It's nasty."