THey are metal!!!! Your hand/nerve endings are temperature sensative - so it detects the difference between your inside body temperature and your outside skin temperature. Metal is a conductor and reflects the temperature it is in. When your skin cools down touching the object the little "nervites" are sending coded messages to your brain that you're touching something cold. Thus the object must be colder than your hand to feel cold and be able to conduct the heat away (thus metal conductor) for you to feel cold! Tah Dah!!!
