A Tabriz workshop known for some of the most unusual designs in the city, woven on a silk foundation at extremely high densities, reportedly about 700 to 1,200 knots per square inch (roughly 108 to 186 per cm²), although dealer listings of its rugs tend to give around 550 to 650 (roughly 85 to 100 per cm²). Even the lower figures sit above the 50 to 500 knots per square inch (about 8 to 78 per cm²) typical of Tabriz rugs as a whole, which makes its rugs exceptionally fine and detailed pieces.
Persian city rugs from Mashhad, Iran's second-largest city, in the north-east, where weaving began in the late Middle Ages. They are known for high knot density (typically above 250 KPSI, roughly 39 per cm², and exceptionally near 1,000, about 155 per cm², on a silk foundation) and intricate flower designs in medallion, medallion-and-corner or allover layouts, in wine-red or burgundy, deep blue, green and cream. The pile is wool on a cotton foundation and higher than in most city rugs; a silk foundation is rare, and newer silk-and-wool pieces add silk to the pile. Rugs of the closed Saber workshop are now collectible, while Astan Quds Razavi remains a well-known name.
A hand-knotted rug woven in Iran, the country called Persia in the West until 1935, in a tradition said to reach back some 2,500 years. It is named after the city, town, region or tribe where it was made (Tabriz, Kashan, Heriz, Baluchi) and belongs to one of three groups: city rugs woven in workshops from a blueprint, village rugs, and tribal rugs, the latter two woven largely from memory. The pile is wool, silk or a blend, on a cotton, wool or silk foundation. Look-alikes woven in Pakistan, India or China are not Persian rugs.
A rug whose pile is entirely silk, woven on a cotton foundation or on a silk foundation; when both are silk, no wool enters the rug. Silk's fineness allows the highest knot density of any Persian rug, roughly 600 to 1,000 knots per square inch (about 9,300 to 15,500 per 10 x 10 cm), so the pile is kept low to show the design, and the fibers give a luminous sheen that shifts with the light. About 90 percent of Qum rugs are silk on both foundation and pile, as are some Isfahan rugs. These are the most expensive Persian rugs; they are delicate and stains are hard to remove, so they suit display, formal rooms or wall hanging rather than dining rooms or homes with pets.
Persian rugs from the city of Qum (Qom), a comparatively young weaving center whose rugs are known for the highest knot density of any Persian type. About nine in ten are pure silk on a silk foundation, at roughly 600 to 1,000 knots per square inch (KPSI; about 93 to 155 per cm²); the rest, with kork wool or silk-and-wool piles, run about 300 to 700 KPSI (about 47 to 108 per cm²). Designs are floral medallions, hunting scenes and pictorials, mostly in soft pastel, ivory, gold and green tones (a pistachio-green field is prized) on light or dark grounds. Newer rugs usually carry a workshop signature, older ones often do not. The local water is said to soften and brighten silk, so silk rugs from across Iran are sent there for washing.
A weaving workshop in Mashhad (Mashad), northeastern Iran, founded around the mid-twentieth century by Abbas Gholi Saber and known for large, high-end rugs of typically about 12 square meters (roughly 129 square feet, or 10 by 13 feet) and up, made on about sixty looms at its peak. Some pieces use a silk foundation, very uncommon among Mashhad rugs, which are usually woven wool on cotton; one such piece is said to reach nearly 1,000 knots per square inch (about 155 per square centimeter). After the founder's death his longtime foreman reportedly kept up the same quality but stopped adding the Saber signature, so signed Saber rugs are rare, collectible and bring higher prices.
A Tabriz workshop founded in the 1990s, young by the standards of Persian rug making, and known for contemporary designs with innovative, unusual color combinations, using a palette of light colors such as cream along with red and yellow. Its rugs carry the workshop's signature and are woven not only on the usual cotton but also on a silk foundation, which allows very high knot densities. The founder's three sons now run the workshop.
A rug whose pile combines silk and wool, usually mostly wool with silk yarn knotted into chosen details such as floral motifs to add sheen and sharpen the pattern. Silk is finer than wool and permits denser knotting, roughly 400 to 700 knots per square inch (about 6,200 to 10,850 per 10 x 10 cm) on a cotton foundation and 500 to 1,000 (about 7,750 to 15,500) on a silk foundation, although Nain, almost always on cotton, drops lower in its coarser la grades, where a higher la number means fewer knots. The wool keeps the pile thick and durable and the price below that of pure silk, though above that of wool alone. Tabriz, Nain, Mashad, Bijar, Isfahan and Qum all weave these rugs, usually with the pile cut short to show the detail.
A rug base in which the warp and weft threads are silk rather than the usual cotton or wool. Silk is finer and thinner, so many more knots fit into each square inch; silk-based rugs typically run about 500 to 1,000 knots per square inch (roughly 78 to 155 per square centimeter). It is found mainly in fine traditional city rugs, most commonly Qum and Isfahan, and also in select Tabriz workshops and some fine YomutTurkmen pieces described in the trade. The pile above may be wool, silk and wool, or pure silk.
Turkmen rugs of the Yomut, counted among the finest Turkmen pieces. Like most Turkmen rugs, Yomut rugs are traditionally wool on wool; finer pieces with a silk foundation under the wool pile are also described in the trade, and in these the silk allows a higher knot count and more detailed drawing than is usual for the type. Grounds run to reds, browns and beige, and the rugs are typically unsigned.