Traditionally, the word "tiara" refers to a high crown, often with the shape of a cylinder narrowed at its top, made of fabric or leather, and richly ornamented. It was used by the kings and emperors of some ancient peoples in Mesopotamia. The Assyrians used to include a pair of bull horns as a decoration and symbol of authority and a circle of short feathers surrounding the tiara's top. The Persian tiara was more similar to a truncated cone, without the horns and feathers but more jewels, and a conic-shaped tip at its top. In Catholicism, the Papal Tiara is a high cap surrounded by three crowns and bearing a globe surmounted by a cross worn by the Pope during certain ceremonies, being the symbol of his authority.