A crystal ball is one of the most well-known magical tools for divination. The use of a crystal ball for divination, the vision of the future, is called crystalomancy, a method of divination in which shiny, reflective objects reveal images and visions of the future.

The crystal ball has become the stereotypical staple of the soothsayer, from gypsies to wizards, witches, and sorcerers. According to tradition, the best crystal is natural. Crystal balls made of artificial glass and crystal are widely used in modern times.

Magical tradition holds that a crystal ball, like other magical tools and talismans, should be magically empowered. This can be done through magical rituals or powers endowed with supernatural entities such as angels. For example, the 16th-century seer John Dee claimed to have received a crystal from the angel Uriel.

In the past, elaborate rituals were performed to peer with a crystal ball, which included invoking certain spirits and working only in auspicious times according to astrology or moon phases. Modern practitioners vary in their rituals. At the very least, the practitioner alters consciousness to facilitate the appearance of visions and the reception of information. Some may not see actual visions in a crystal but still receive information. The crystal itself is not considered to hold any magical power, but is a means for the practitioner to access psychic abilities.

The peculiarity of this consultation is that what is seen is a kind of scene that speaks to the future like a dream but more nebulous.