Nest Of Boxes Peerless

A spectator is asked for the loan of a coin which is duly marked by it's owner. Coin is then vanished by the magician. Pior to this, the magician has displayed a small brass box which was left in full view. Following the vanish, the small box is opened by the spectator and a sound brass box is found. This is opened only to disclose another, even smaller box. Finally the fourth and hopefully last box is opened. To the spectators surprise, his missing marked coin is found within.