Luxury rugs and carpets sometimes use silk. Until the late 19th century natural dyes, made from mineral pigments, plant materials, and animals and insects, were used for coloring the yarns. Synthetic dyes were produced in Europe beginning in the mid-19th century and were soon introduced into Asia and North America. These dyes were popular because of their inexpensiveness and brilliant color, but they tended to fade and deteriorate quickly. The Asian tradition is older and richer than the Western.
Most Asian carpets are rectangular, although other shapes are occasionally found.
Nearly all designs are divided into a border and a field. The earliest Islamic pile carpets from the Middle East date from the 13th century. Persian rugs of this period are characterized by balanced compositions, strong color contrasts, and multilayered patterns. Some of the most important carpet types of the 16th and 17th centuries are associated with the city of Ushak in western Turkey, which was one of the centers of court weaving in the Ottoman Empire. Prayer rugs, star-patterned rugs, medallion carpets, and bird patterns are ascribed to Ushak artisans.