A woman bit down on a rare pearl while eating a meal of clams and other seafood at an Italian restaurant in Washington state.

Lindsay Hasz and her husband Chris were eating at Montalcino Ristorante Italiano in Issaquah recently when she bit into something hard in her entree, KOMO-TV said. Ms Hasz said she was not sure what it was but put it in her pocket and went home to do research.

She took it to a gemologist who determined it was a Quahog purple pearl worth about $600.

Ted Irwin, of Northwest Geological Laboratory, said the find is rare, with only one in a few million being of gem quality. Ms Hasz said she may have the pearl made into a necklace.