The magician shows a U.S. quarter and a bottle. It appears that he placed it inside the bottle--although the coin is clearly too large to fit into the opening at the top.
A coin and a bottle. The magician display an empty bottle and a U.S. quarter and with a gesture the coin seems to penetrate the bottle although it appears too large to fit through the opening at the top. The magician removes the coin to displays both in perfect order.
Another effect can be presented where the magician appears to bite the coin in nearly half--then spits the piece back and the coin is restored.