well, if he swallowed jewellery then the acids in his tummy would probably be strong enough to clean metal.............so they's come out all shiny..........lol............or yucky depending on whether or not he's had his shredded wheat...............lol...........
jewelry, not sure if would be very comforable though, it may get stuck
espcially if it was larger than a pearl, too many edges, you may be able to use a magnet to get it out.
I think I'll stick with the old spit & shine approach.