[expand]The pile knot created three-dimensional surface. Each knot wrapped around two (occasionally one or three) warp threads, its loose ends extending outward forming pile. The two primary knot types—Turkish/Ghiordes knot (symmetrical) and Persian/Senneh knot (asymmetrical)—produced slightly different visual and structural effects. The knot choice was regional tradition and personal preference rather than absolute superiority, both techniques producing quality rugs when executed properly.
The knot density measured in knots per square inch (or square centimeter) indicated fineness and labor investment. Coarse rugs might have 25-50 knots per square inch—adequate for utilitarian purposes, produced relatively quickly. Medium density rugs achieved 100-200 knots per square inch—balancing quality with reasonable production time. Fine rugs exceeded 300 knots per square inch—requiring magnifying vision, extreme patience, and resulting in textile approaching tapestry fineness. The density directly correlated with value—finer rugs cost more, took longer to produce, and demonstrated superior skill.
The pile cutting established final surface character. After several rows of knots were tied and beaten down with weft, the pile loops were cut creating individual tufts. The cutting technique affected texture—shearing precisely at knot base created uniform smooth surface, leaving slightly longer pile produced softer more luxurious feel, irregular cutting created texture variation. The final trimming occurred after rug completion, skilled shearers using large scissors to even pile height, sometimes carving patterns through deliberate height variations creating sculptural relief effects.
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