When you think of Oriental rugs you probably think first of wool. Wool is the most prominent fiber for rugs. It is also the oldest known rug fiber. The Pazyryk rug, discovered in Kazakhstan in 1949 is about 2,500 years old. Wool face yarns are constructed with approximately 225 symmetrical knots (also known as Turkish or Ghiordes knots) per inch. Many of the design elements including motifs and borders continue to be used in Turkmen rugs.
Wool is not the only fiber used. Other animal hair products such as goat hair are also used along with cotton, which is common in foundation yarns.
The patterns, symbols, and colors give clues about the origin of the rug. A Chinese-made rug may include icons for dragons, pagodas, or other Chinese imagery. Some Afghani rugs, often sold to soldiers stationed there may depict weapons of war or maps of the country or certain provinces. However, popular patterns travel easily and may be reproduced in many locales. For example, rugs with a Persian pattern are also made in India and China. Such are called Indo-Persian or Sino-Persian rugs. The first part of the name indicates the origin and the second part is the style. Weavers may become emigrants or refugees to escape warfare for economic and other reasons. They take their preferences in the design along with their skills to new locations.
Rug construction is often a more reliable indicator of the source than design. Check the fibers used both in the face and in the foundation. Are the fringes a continuation of the warp yarns or something sewn on after the rug was woven? The knots that form the fringe can give a clue. For example, the knots on Chinese rugs tend to be very even and are said to resemble a pineapple or a barrel.
Take note of the transition from the main body of the rug to the fringe. Is there a narrow band with no face fibers (called a kilim strip)? Are there colored weft threads throughout the body of the rug or near the fringe? What about the edge treatment? Have the edges been finished by wrapping 2, 3, or perhaps 4 warp threads together? Do the sides and edges of the rug look square or is the rug dimensionally challenged with the sides appearing wavy?
All those construction factors and more are clues to where the rug was woven. As an example, tribal rugs woven by nomadic peoples are more likely to use wool on wool rather than cotton foundation. Perhaps goat hair is seen on the edge finish. Due to the more portable style of loom used, the rugs are likely to be smaller and seldom square. The patterns are chiefly geometric with more straight lines and fewer curves, fewer floral patterns, and less intricate designs. The weft yarns may vary in size with some portions of the weft thicker than others. The spinning of the yarn is less controlled than in an industrial city environment.
Construction’s Impact on Cleaning
Wool and other hair fibers are excellent at hiding dirt. To an extent, wool tends to shed dry particles of soil and water. Where does the dirt go? Deeper in the pile, down to the foundation. Wool rugs are also likely to have a much more dense pile than the Saxony or Berber carpet in your living room. Rugs fibers hold pounds of the soil before they begin to look soiled. Dirt is trapped by macro-occlusion (in the small spaces between yarns) and by micro-occlusion (soil held in the space between individual filaments of the yarn).
The denser the pile the more soil can be held. Rugs with depressed warps effectively make the foundation thicker and an even better hiding place for dry soils. Expect to spend significantly more time removing dry soils from rugs when compared to installed carpets. More time and agitation are needed to loosen soil from thicker rugs.
On the other hand, flat-woven rugs have no pile to trap dirt. Dusting (dry soil removal) will be much simpler. Flat weaves are reversible and both sides have probably been walked on. So, you will need to clean the front and back. Any soil, spots, or stains that are not removed will be visible. Time saved in dusting may be balanced with additional time required to patiently remove stains. Remember, like a doctor the rug specialist must abide by the motto, “First, do no harm.” Our zeal to remove every remnant of stain can get us into trouble. The high pH cleaners, oxidizers, and reducers that you may have come to depend upon when cleaning synthetic carpets can all harm wool. When cleaning, it is recommended to use the mildest oxidizers and reducers. In addition, provide your client the information they need to give informed consent before you continue.
A complex design will be more forgiving at hiding any remaining soil or stains. By contrast, a large open field with a light color is more likely to reveal any unevenness in appearance after cleaning.
When cleaning cotton fringes, it is good to keep in mind that the natural color is not pure white. Over-white fringes may indicate that previous cleaning attempts have done damage, weakening the cotton. Strands of fringe can be pulled loose by the vacuum cleaner or by agitation during cleaning. Document the condition of the rug including fringes before you begin work. Be cautious when using any treatments to brighten or whiten the fringe. You don’t want to be responsible for the damage.