The Zarrow Shuffle is one of the most popular false shuffles used today. While giving the impression of a legitimate tabled riffle shuffle, the original order of the cards is retained. The shuffle was devised and published by Herb Zarrow in 1957 in the magic periodical The New Phoenix, Issue No. 347. Other sources of the move include "Card College Vol. 3" by Roberto Giobbi, "By Forces Unseen" by Ernest Earick, and "Riffle Shuffle Systems" by Edward Marlo. There have been numerous false shuffles similar to the Zarrow Shuffle long before its publication. Even so, the Zarrow Shuffle has gained popularity among magicians and card cheats alike.
When executing this sleight, it's best to use a multiple card cover block, rather than a single card slip cut. This provides more cover for the move. Also, it's good practice to push both halves together at once than only pushing one into the other. It will make the square up far more natural. You may also want to have your fingers in the front to be at a 45 degree angle from the table, not perpendicular. This adjustment will provide more cover in the front, allowing you to hide the gap.
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