Really, I Can't Find It

"Ha ha ha, very funny. Really, where is it?" Jon looked up at Karyn. "I'm not joking. I really must have dropped it. Probably when I slipped." "You what?" "I slipped in the hall. It was kind of embarrasing. I'd rather not talk about it." "Fine. But maybe we should go look for it and get it before someone else does." "Good idea." Jon and Karyn stood up, left the lunch room and walked to where Jon took his "tumble". They looked around for a while, without finding anything. "Are you sure you had it with you when you slipped?" asked Karyn. "Sure. I know I did." Jon touched his forehead. "This is NOT good. We need to find that rock."