The material used most often in Oriental rugs is the glossy and supple wool of sheep. Other common materials include goat's hair, camel's hair, cotton and silk.
Wool is provided by the numerous flocks, often tended by nomadic shepherds, that graze in vast, undeveloped areas. The finest wool is thought to come from a region, often referred to as Kurdistan, where the western part of Persia borders Turkey. Wool from Khorasan and Kirman is famous for being fine and velvety, while wool from the Caucasus and Central Asia is prized for being strong and lustrous.
The nomadic peoples usually shear the animals toward the end of spring. First, the animals are washed by the side of a river or near a well. The wool undergoes a second washing after the clipping. Then, it is trampled underfoot and dried in the open air. The wool is spun according to age-old methods. Holding a quantity of wool under arm, the spinner twists the threads and wraps them around a rod.
The material for the warp and weft threads varies from region to region. Cotton is used extensively in Persia. In Turkey, particularly in mechanized production, the warp and weft also tend to be of cotton. And the use of cotton for warp and weft threads is increasingly replacing wool in the Caucasus. Warp threads of goat's hair frequently are found in Afghan, Baluchistan and Bukhara rugs. Because it is not long-wearing, camel's hair has lost favor with the nomads of Turkestan.
At times, silk has been used for both the warp and weft threads, giving the rug a sumptuous appearance. Since the silk was expensive and did not wear well, it typically was reserved for carpets woven for holy places, for prayer rugs and for royalty.
Sheep's wool continues to be the material of choice for the pile of Oriental rugs. The wool of the pile usually is two-ply, meaning that two threads have been twisted together. It is from the materials used that Oriental rugs obtain their wonderful sheen.