An astounding and seemingly IMPOSSIBLE miracle!
You show a wallet with a small square in the middle. A mirror, attached to a ribbon, is passed around for inspection, then inserted into the wallet. A die (singular for dice) is also inspected. The die is placed in the square in the wallet, then, bit by bit, it very slowly sinks until it completely penetrates the mirror and drops to the floor! The die and mirror can be once more passed around for examination.