Have you ever noticed the difference in sound on dropping and iron sheet/ plate, a metal coin, and a piece of coal on floor? If not try it now. Do you note any difference in sound?

Explanation

Yes, the iron sheet/plate and a metal coin when dropped on the floor, produce ringing sound. But, a coal piece, when dropped on the ground, does not produce any ringing sound. One can try the process any number of time but one cannot produce any ringing sound out of dropping coal on the floor. Whereas in case of a metal piece, on dropping on the floor, a metallic sound is produced. This is the difference.