Fake snow is any product which simulates the appearance and texture of snow, without being made from frozen crystalline water. Fake snow has been made from many materials. In the early 1900s decorative snow was sometimes made from borax flakes and even ammonia. Before the dangers of asbestos were known, the substance was sold for Christmas tree decoration. It was also used to simulate snow in films, including The Wizard of Oz and Citizen Kane.