The "folding coin in a bottle" magic trick is accomplished using a specially gimmicked "folding coin" which has been precisely laser-cut so that it can fold in half or in thirds, allowing it to be inserted into and removed from a normal bottle with a narrow neck. Here's how the trick generally works: The Gimmick: The magician uses a real coin that has a hidden, seamless cut. This allows the coin to be bent or folded small enough to fit through the neck of the bottle. The Performance: The magician can even borrow a coin and bottle from a spectator, or use their own. The magician demonstrates the coin is a normal, solid coin and the bottle is an ordinary empty bottle. With some misdirection and sleight of hand, the magician folds the coin and pushes it through the neck of the bottle.
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