The materials from which rugs are made, named in order of the ratio in which they are used, are wool, goats' hair, camels' hair, cotton, silk, and hemp.

Wool.—The wool produced in the colder provinces is softer and better than that produced in the warmer provinces. Likewise that produced at a high altitude is superior to that from a lower altitude. The quality of the pasturage plays a most important part in the quality of the wool. For this reason no better wool is to be found anywhere in the world than from the provinces of Khorasan and Kurdistan. Very often the sheep are covered over with a sheet to protect and keep the wool in a clean, lustrous condition. The quality of the wool also depends to no small extent upon the age of the sheep from which it is taken, that from the young lambs being softer and more pliable than that from the older animals. The softest and most lustrous wool is that which is obtained by combing the sheep in winter and is known as kurk. From this some of the choicest prayer rugs are made.

Goats' Hair.—From the goats of some localities, especially in Asia Minor and Turkestan, is obtained a soft down which is used to a large extent in the manufacture of rugs. The straight hair of the goat is also used. It is of a light brown color and, as it will not dye well, is sometimes used without dyeing to produce brown grounds, as in some of the Kurdistan products. It is quite commonly used as a selvage and fringe in the Turkoman products. When wet it curls so tightly that it is difficult to spin it, therefore it is not always washed. This accounts for the strong odor which is especially noticeable in warm weather.

Mohair is obtained from the Angora goat of Asia Minor, while cashmere consists of the soft under-wool of the Cashmere goat of Tibet.

Camels' Hair.—In Eastern Persia, Afghanistan, and Beluchistan are camels which produce a long woolly hair suitable for rug weaving which is never dyed, is silky and soft, has phenomenal durability and is used quite freely in the Hamadan, Mosul, and Beluchistan products. It is more expensive than sheep's wool but has one great drawback in that on the muggy days of summer it has a disagreeable odor. Most of the alleged camels' hair of commerce is a goats' hair pure and simple.

Cotton.—The majority of the finer Persian rugs have cotton warp and woof. It makes a much lighter, better and more compact foundation on which to tie the pile, and a rug with such a foundation will hold its shape much better. Seldom is cotton used for the pile excepting once in a great while a Bokhara may be found with small portions of the white worked in cotton.

Silk.—In the regions bordering on the Caspian Sea and in some parts of China where silk is plentiful it is used to quite an extent in the making of rugs, not only for the nap but frequently for the warp and woof as well. It makes a beautiful fabric, but of course will not wear like wool.

Hemp.—Hemp is seldom used in rug making for the reason that it rots quickly after being wet and the entire fabric is soon gone.

Preparation of the Wool.—After being sorted, the wool is taken to a brook and washed thoroughly at intervals in the cold running water for several times until all foreign matters are removed, leaving the animal fat which gives it the soft, silky appearance. The results of washing depend to a certain extent upon the quality of the water used in the process, soft water giving much better results than does the hard.

After a thorough bleaching in the sun's rays it is placed in a stone vessel, covered with a mixture of flour and starch, then pounded with wooden mallets, after which it is again washed in running water for several hours and again dried in the sun. Under this process it shrinks in weight from forty to fifty per cent., and after being spun the yarn is sold everywhere for the same price as twice the amount of the raw material.

It is spun in three different ways. That which is intended for the warp is spun tightly and of medium thickness, that for the woof rather fine, and that for the pile heavy and loose.

There are so many different natural shades of wool that much of it can be utilized in its natural color. The dyeing is always done in the yarn, never in the loose fibres, and will be explained in the chapter under Dyes.