Long long ago, people\'s first attempts to mark playing cards involved bends, crimps and tiny pinprick bumps. Later, the first designs appeared on the back of playing cards. Hustlers have used different kinds of inks, pigments and scratches to add or remove lines or patterns from the back of the card design.
More recently, science and technology have also enhanced marked-card techniques. Modern technologies are variations of shade techniques. Traditional block-out and cut-out work have the disadvantage that they must be read close-up, because the marks are small. And now, players can read the marks with the help of infrared contact lenses and sunglasses.
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