Persian & Oriental silk rugs are the most intricate, and often most valuable, of all hand-knotted rugs. The fine yet strong silk fibres used in these rugs allow more knots per square inch to be tied giving a clearer pattern with more detail and increased likeness to real-life, a good analogy being that of an HDTV over a regular TV. The most valuable silk rugs are 100% silk from the warp and weft to the pile. Because of their silk foundation there can be more warp strings (visible as tassles or fringes at the ends of the rug) across with width - meaning more knots can be tied in a given area. With the more expensive materials coupled with finer knot counts comes more skilled artisans. Below is a Persian Qom silk rug in a relatively large size, the rug below is 3x2m whereas most silk rugs are much smaller (often around 1.5x1m). Many Persian & Oriental rugs are wool, often &＃39;kork&＃39; wool or merino and have silk details. Included in these are many rugs woven in Nain and Tabriz, often the white areas in these fine rugs use silk details to give them added luxury and depth. Other rugs are knotted in wool but based on a silk, rather than cotton, foundation. www.digisilkroad.com