Magnetic Colors

The spectator gives the deck a riffle shuffle. Although the shuffle appears to be completely random, the spectator finds on dealing off pairs of cards that every pair contains exactly one red and one black card!

Method: This routine was independently devised by Gene Fin-nell, Norman Gilbreath and others. Preparation consists of arranging the deck so that the colors alternate red-black-red-black from top to bottom.

Cut the deck at about the midpoint. The only stipulation is that there is a red card on the bottom of one half and a black card on the bottom of the other half. Place the two packets side by side. Tell the spectator you are going to control the way he shuffles the deck even though you will not touch the cards.

The spectator gives the deck one riffle shuffle. He then deals pairs of cards off the top and turns each pair face up. He should be surprised to discover that each pair contains one red card and one black card.

Laymen think that a riffle shuffle destroys any possible order of the cards. They are therefore baffled to discover that even though they shuffled the deck, the cards are still in order!