I bought a simple freshwater pearl necklace from Mandarin Jewelry at the Gem & Jewelry Show in San Mateo. It was a great price, but the strand was a little long for me because I have a thin neck and prefer more of a choker style. Since I live in San Francisco, they said I could simply take the necklace to their office on Post Street and they would shorten(re-string) it for no cost. So, I took the pearl necklace in and they did exactly that. It took them only 30 minutes, they charged nothing, and they were as friendly as could be. Both over the phone and in person, they made me feel very welcome.