What to do when they come in JUST FOR A RING SIZE?

 If someone comes in just to get their ring size and you suspect they are buying online, here are approaches you can take:

 Will of Bockemuehl Jewelers suggests telling the person there are too many variables like thickness of the gold, ect to give them a true size.

  Paul Reiser brings up the good point that they are IN your store. Think of the millions of shoppers who never even come in. Once you have them in your store do all you can to win that sale. Maybe say something like this. "I know it's bold of me but I'm guessing you are getting a ring elsewhere. All I ask is that you give me one chance to impress you. I am your neighborhood jeweler after all. What have you seen that you are interested in? I can make anything you can dream up..."