Where does this one-prong grounding clip go?

I am reassembling my iPhone 4S and have a small one-prong grounding clip that fell out after I removed the logic board and before I could see where it came from. It is NOT the camera grounding clip, I have that and know where it goes. It is a black rectangle 5mm x 3mm with a screw hole offset towards one side. A small 2.5mm ground prong sticks off perpendicularly from the opposite corner from the hole. any help on its location and orientation would be a huge help. I would post a photo but I can't seem to figure out how.