Hand knotted rugs possess certain inherent characteristics which aid in their uniqueness. Color variations in the field and or border, known as abrash, are a beautiful example of such a characteristic. The term abrash, from the Arabic word for mottled, is typically used to denote color changes or striations running horizontally across the face of a rug. These color changes will appear within the same color ie., a light blue field may have striations of darker blue. However, abrash can also refer to a more general variation of color throughout a certain field of color causing the area to have a mottled appearance.
Abrash results from variations in the dyeing process. Most commonly, different dye lots may not result in a perfect match, particularly if small dye batches are used. The weaver runs out of one batch and restarts with another which may result in a shade difference. Differences within the same dye lot are also possible. Variations in the yarn density and twist, especially with hand spun yarns, allow for different absorption rates of dyes. In addition, the time spent in the dye bath may also affect absorption rates since the yarns on the outside of the skein will absorb color faster than the yarns on the inside of the skein.
Occasionally abrash may appear more apparent following a professional cleaning. Sometimes the true colors are obscured by soiling, and often the rug owner will very closely inspect the rug noticing slight variations which were pre-existing, but have long been forgotten.
Although some may prefer consistent and precise coloring in their rugs, abrash is often prized as a beautiful characteristic of an oriental or hand knotted rug. Many machine made rugs often incorporate abrash in their designs to enhance their appeal. It is often discussed in the rug community how much of abrash is an “accident” of the dye process or how much is intentional by the weaver. The question only adds to the mystique of oriental rugs.