What Wishing Stone?

At lunch time, Karyn sought out Jon, who was sitting at his usual table. "So, I was thinking about what we could do with the stone after school ..." Karyn began. Jon got a confused look on his face. "Stone?" "Yeah, the *wishing* stone?" "Wishing stone? Karyn, what are you talking about?" Now Karyn was getting concerned. At first she thought he was being funny, but she was starting to believe that he had somehow forgotten about the stone. "The wishing stone that you got from your grandfather ... as your inheritance." "Karyn, I didn't get an inheritance." Now she had reason to panic.