We’ve all become used to seeing fakes for sale on the sidewalks, but as counterfeiters have grown ever more skilled at reproducing luxury goods, more and more of us risk being the victims of unwittingly purchasing a knockoff. Just ask my fashionable colleague who had this rude awakening at a recent cocktail party: She was nibbling on canapés, a designer bag in the crook of her arm, when a publicist for the brand came over to chat and asked her where she’d bought her handbag. My colleague had received it from her boyfriend — a much-loved first-anniversary gift — and he’d found it online at a great price. “That bag is a fake,” the publicist informed her. My colleague asked her how she could tell and was shown the subtle difference in stitching — almost invisible to the naked eye — that separated her handbag from the genuine thing. She was mortified.

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