The Crystal Ball

Used by psychic readers for centuries, the crystal ball is one of the most recognizable items in the world of fortune telling. It was first used by Celtic tribes in the same way it is used today- to see into the past, present, and future of a clients life. Psychics, high priests and priestesses, gypsies, and other supposed mystics believe in the many powers of crystal balls in the process called "scrying". They were originally made of beryllium but are now more commonly made of quartz, both of which are clear, reflective gemstones. Several unproven claims about the usage of crystal balls exist such as, clearing the mind of the psychic, assisting in entering trance-like states, and strengthening their powers of clairvoyance.

All of these claims are almost impossible to prove because they depend on the belief of psychic abilities to begin with. A psychic medium may claim any of these effects and uses for crystal balls, but anyone without supposed psychic powers would be unable to witness these effects. Until then, people who are believers will continue paying for the services of psychics and crystal balls.

http://www.psychicreviewonline.com/psychic-articles/all-about-psychic-readers/this-history-behind-the-crystal-ball/

http://www.the-crystal-ball.com/crystal-ball-history.php