Crystal ball

Crystal or glass ball and common fortune telling object

A crystal ball is a crystal or glass ball commonly used in fortune-telling. It is generally associated with the performance of clairvoyance and scrying. Used since Antiquity, crystal balls have had a broad reputation with witchcraft, including modern times with charlatan acts and amusements at circus venues, festivals, etc. Other names for the thing include crystal sphere, scrying ball, shew/show(ing) stone, and more variants by dialect.

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