BijarRugs from the city of Bijar in Kurdistan province, northwestern Iran, and the villages around it; the name covers both fine and coarse double-wefted pieces, woven by Kurdish tribes and, in workshops, Afshar weavers. Nicknamed the “iron rugs” of Iran, they are among the heaviest rugs for their size: double wefts, symmetrical (Turkish) knots, and rows beaten down hard, often while the wool is kept wet, give a thick, dense pile. Designs run from floral, Herati, and medallion to geometric, drawing on Isfahan and Kashan as well as Russian, Caucasian, and European sources (a French-style rose bouquet among them), in jewel tones of rust, red, beige, and navy. Bijars are often small rugs or runners, large sizes are rare, and the flat-woven ends and fringes are typically braided.See in the carpet dictionary stands in the highlands of Kurdistan Province, at its north-eastern edge, in the north-west of Iran. Sanandaj lies to the south-west, Zanjan to the north-east and Hamadan to the south-east. The town is the seat of Bijar County and was historically the chief place of the Garrus district, which is why older pieces are sometimes labelled Bijar-e Garrus. As a rug name it covers far more than the town itself: the surrounding Kurdish villages weave under the same name, and the trade applies it to both the fine and the coarse double-weftedA construction in which two weft threads, rather than one, are run through the warp between successive rows of knots. The doubled weft covers the foundation, so on the back of a finely and tightly woven rug only knots and weft show, without the white flecks of warp that give away a single-weft rug, and the rug is thicker, denser and heavier. Bijar and Heriz are typical double-wefted types, as are finely woven Persian rugs in general.See in the carpet dictionary rugs of the wider Kurdistan area. Production is organized village by village rather than in one city workshop, and what holds the name together is not a house style but a way of building the fabric.

Weaving here belongs to the Kurdish tribes endemic to the district, and the trade still uses tribal names as sub-labels: Gerus, also written Garrus, alongside Halvai. The Afshar, a Turkic group long settled in the area rather than a Kurdish one, produced many of the workshop-grade pieces and lends its name to another group of them. That mix of hands explains something that puzzles first-time buyers, since few Persian region names cover such a wide spread of patterns, palettes and degrees of fineness. Two rugs that look as though they came from opposite ends of the country can both be entirely correct Bijars.

DensityA measure of how tightly a carpet is packed. In machine-made carpet it describes the fibers in the pile and is calculated by multiplying the face weight by 36 and dividing by the pile height; higher density generally indicates better durability and performance. In hand-knotted rugs it means knot density (KPSI, knots per square inch), counted on the back and averaged over several areas (150 KPSI is about 23 knots per cm²). Like image resolution, higher density allows finer curves and sharper designs, usually with a lower-trimmed pile and more labor, but it is not the sole measure of quality: bold geometric village rugs are made at low to medium density.See in the carpet dictionary is the point of the weave. These rugs are double-wefted, and every row of knots is beaten down hard before the next is tied, so the fabric compacts as it grows. Weavers traditionally kept the woolA natural animal fiber used for the pile, and in some rugs also the foundation, of high-quality rugs. It is durable, resilient, stain resistant and flame resistant, feels soft and cushioned underfoot, insulates against cold, and takes up dye readily and holds it for many years. It also traps dust particles, which helps reduce allergic reactions. Quality depends above all on where the sheep graze: high-elevation pastures and good feed give thicker, oilier wool, with Manchester, New Zealand and Ghazni wools the best-known prized examples. Early-spring shearing and hand spinning (finer, softer thread than machine spinning) improve it further, while thin, dry wool from dead sheep goes into cheaper rugs.See in the carpet dictionary damp while working, which let them pound the wefts and knots into place with far more force than dry yarn allows. The result is stiff, heavy and almost board-like when new, and it is the reason for the nickname the iron rugs of Iran. For their size they are probably the heaviest carpets made anywhere in the country.

Identification comes down to the weave rather than the pattern, because Bijar designs overlap with those of the central Iranian city workshops, Kashan and Isfahan among them, and with closer neighbours such as Zanjan. The knot is the symmetrical one, usually called the Turkish knotOne of the two main knots of hand-knotted rugs, also called the symmetrical knot (the other being the asymmetrical Persian or Senneh knot). The yarn is looped around two adjacent warp threads with both ends emerging between them, so the back shows small, even, squarish knot heads; weavers often tie it with a hook. Named after the town of Ghiordes (modern Gördes) in Turkey, it is typical of Turkey, the Caucasus and northwestern Iran (Tabriz, Bijar, Heriz, village Hamadan), where Seljuk Turks are said to have introduced it, and gives a durable, precise pile. The Persian knot is often credited with finer detail, yet knot type is a tendency, not a limit: Tabriz rugs woven with the Turkish knot reach about 500 knots per square inch (roughly 78 per cm²).See in the carpet dictionary, in contrast to the asymmetrical Persian knotThe asymmetrical knot of hand-knotted rugs, the counterpart of the symmetrical Turkish (Ghiordes) knot. The weaver wraps the yarn around one warp thread and passes it under the neighboring one, usually working by hand without a hook. On the back of the rug the knots look staggered or diagonal rather than like tidy squares, and the pile feels softer; the knot permits finer detail and higher knot density. In Iran, a rule of thumb ties it to the central, eastern, and southern rugs (Kashan, Isfahan, Nain, Kerman), while the northwest and west favor the Turkish knot, though exceptions exist. Fine curvilinear florals are often credited to it, but Turkish-knot rugs can be just as intricate.See in the carpet dictionary used across central Iran; the usual explanation is Turkic settlement in the north-west, though no date is attached to it. Turn one of these rugs over and the back is closed: the double weft covers the warps, so you will not see the zig-zag of white specks that single-weftedA construction in which the weaver passes just one weft thread between successive rows of knots. Because the warp is not fully covered, the back of the rug shows a zigzag of small white foundation specks, an easy way to recognize it, and the pile tends to be thinner and lower than in double-weft weaving. Single weft is standard practice in the greater Hamadan area, from Hamadan, Karaja and Mehraban rugs to Senneh and many Kurdish tribal pieces, and in the Hamadan-influenced type of Malayer rug.See in the carpet dictionary village rugs across the greater Hamadan area, many Kurdish weaves among them, show on the reverse.

A second tell sits at the ends. Where the pileThe surface of a rug or carpet, made of upright fibers in cut tufts or loops. In a hand-knotted rug it is formed by the cut ends of thousands of wool or silk knots tied onto the warp row by row, trimmed lightly during weaving and given its final height by shearing at finishing. Pile thickness, measured from the back of the rug to the top of the pile, typically runs from low, about 1/8 to 1/4 inch (3 to 6 mm), to high, about 1/2 to 5/8 inch (13 to 16 mm). Fine, dense designs are cut short to keep the pattern sharp; higher pile suits traffic and heavy furniture, lower pile suits door clearance and humid rooms.See in the carpet dictionary stops, most rugs finish with a plain woven kilimA flat-woven rug with no pile, traditionally made in Turkey, Iran, Afghanistan, and the Balkans. Colored weft threads are interlaced with the warp without knots, so both sides look alike. The fibers are typically wool, cotton, or goat hair, and natural dyes often give slight shade variations that are normal, not flaws. Its low profile clears doors easily, and it can hang as wall art. In a knotted rug, "kilim" also names the flat-woven band at each end, where extra weft rows secure the ends beside the fringe.See in the carpet dictionary band before the fringe; here that band is over-braided, and the fringe itself is frequently braided as well. It is a small piece of finishing, easy to overlook, and one of the few details that is genuinely regional rather than shared with half of Iran. Together with the closed back and the symmetrical knot, it is enough to place a rug without reference to its design at all.

Knot densityThe number of knots in one square inch of a hand-knotted rug (KPSI; 1 KPSI is about 15.5 knots per 10 x 10 cm), counted on the back with a ruler by multiplying the knots along one inch of height by those along one inch of width, averaged over two or three areas. More knots give sharper detail, like a higher-resolution screen, and, all else equal, somewhat more durability and a higher price, but density alone does not grade quality: Heriz and Bijar are durable at low to medium counts, while floral curvilinear designs blur without enough knots. Figures run from under about 80 for coarse tribal weaves such as Gabbeh and Qashqai, through roughly 120 to 225 for many village rugs and 300 to 700 for fine city rugs such as Nain and Isfahan, to 600 to 1,000 or more for pure silk Qum.See in the carpet dictionary, by contrast, is unremarkable. Counts fall in the low to medium range, which tends to alarm buyers who have been told that knots per square inch (KPSI) is the measure of quality. This region is the standing argument against that idea: these are among the most durable rugs woven in Iran, and the durability comes from compaction and from the sheer weight of wool in the pile, not from fineness. Small pieces and the finer village grades do run higher, but a finely knotted silk rug from a city workshop still will not take hallway traffic the way a coarse Bijar does.

Standard construction is a cotton foundation with a wool pile, the wool coming from the local highland clip. Silk turns up occasionally, though it is very much a minority line: cotton foundation still, silk used only as highlights within a wool pile, always on a floral pattern, usually over grounds of cream, rust or black with touches of green, peach, brown and blue. Those pieces are knotted finer than the ordinary village weave and are generally small, which is how most buyers meet them, and a woven signature in the field is common on them.

Color is where the Kurdish hand shows. Fields are worked in rust, red, beige and dark navy, with highlights picked out in light green, rose, light blue, yellow and black. The effect is jewel-like rather than muted, and the strong colors sit together without the rug becoming noisy, a balance that is harder to achieve than it looks and one these weavers have long been credited with. A rug of this kind will usually decide the palette of the room it goes into rather than blend into one already there.

Pattern repertoire is broad: dense all-over florals, classical geometry, a single large center medallionA large motif at the center of a rug's field, around which the rest of the design is organized; the large central medallion is said to have been introduced in the Safavid era (16th-17th centuries). Floral medallions, typical of city rugs such as Tabriz, Kashan and Sarouk, are often read as a lotus blossom, and the motif has also been read as mirroring the interior dome of a mosque; geometric ones, often hexagonal or diamond-shaped, mark village and tribal rugs such as Heriz and Zanjan. A medallion may stand alone, come with four corner pieces, be flanked by smaller medallions above and below, or repeat down a runner. Rugs with no central motif are called allover. In a well-made rug the medallion sits at the center and the corners mirror one another, as closely as handwork allows.See in the carpet dictionary, and the Herati or fish designA classic Persian design built on a diamond repeated across the field, with a small flower or leaves inside each diamond and curved leaves at its sides; the leaves are read as stylized fish, said to circle a lotus. The name comes from Herat, the city in Afghanistan where the design is said to originate; it is also called the fish design, and Mahi means “fish” in Persian. It is one of the three main design families, woven as an allover pattern or around a central medallion with diamonds inside and outside it, and it sometimes appears as a thin border. It is common in Tabriz, Sarouk, Mashhad, Moud, Bijar, Hamadan, Abadeh, Zanjan, Kerman and Kashan rugs.See in the carpet dictionary, of which Bijar is one of the recognized homes alongside Tabriz, SaroukPopular, durable Persian city rugs from Sarouk, a town in central Iran about 50 km (31 miles) north of Arak, prominent from the 19th century and exported to Europe and America. A cotton foundation carries a medium-to-thick wool pile, at times with silk highlights, usually tied with the Persian knot (some older pieces use the Turkish knot) at medium-to-high density of up to about 320 knots per square inch (roughly 50 per cm²). Floral, medallion and allover designs, with some Herati, boteh and pictorial patterns, appear on beige, ivory, cream, navy or red fields, the red leaning toward orange or rust, usually with a thin secondary border. American Sarouks, woven mainly in the 1920s and 1930s, adapted designs and colors to U.S. taste, and many were re-dyed to a preferred rose red.See in the carpet dictionary, Zanjan and Hamadan. Recurring local habits include a broad ribbon-like contour drawn around the medallion and a narrow Herati border. The region also handles open fields unusually well, so large areas of plain ground that would look empty on another weave read as deliberate and calm here.

Sources for those patterns reach well beyond Iran. Alongside borrowings from the city workshops of Isfahan and Kashan, weavers here drew on Caucasian and Russian designs, and on European ones. The clearest example is a bouquet-of-roses pattern lifted from French carpets, which entered the repertoire during the nineteenth-century revival, when Persian weaving was increasingly made with European buyers in mind. A rug from a Kurdish village carrying a French floral arrangement in a Turkish knot is not a contradiction; it is ordinary for this region.

Sizes run small. Scatter rugs and runners are what the district weaves most, and a large Bijar is comparatively rare, which is worth knowing before settling on one for a dining room. The weight works in favour of the smaller formats: the fabric lies flat, resists rucking and stays where it is put, which is exactly what is wanted from a runner or from a piece inside a doorway.

Pile height sits at the high end, in the same company as HerizBold village rugs from the Heriz area of northwestern Iran, near Tabriz, and the best-known of all Persian village rugs. A coarse, tough wool pile on a cotton foundation, usually double-wefted for extra thickness, and a low-to-medium knot density (commonly quoted at about 120 to 170 KPSI, roughly 1,900 to 2,600 per 10 by 10 cm) make them very durable; the wool's strength is traditionally credited to copper-bearing mountain water. The classic design is a large angular medallion with four corner pieces, sometimes an allover layout, in a rust red traditionally credited to copper minerals in the local river, with dark navy and cream. Bakshaish and Serapi, the latter now over a century old, are their older forms.See in the carpet dictionary and Mashad, so these are rugs for places that take punishment: entrance halls, foyers, landings and any route everyone walks. One caveat for a home office is that a thick pile makes a desk chair difficult to roll, so a chair mat and a yearly rotation are worth the trouble. If nothing can be found in the size you need, Zanjan is the closest substitute: geometric, deep reds and browns, a pile almost as thick, differing mainly in its dyes.

A Persian rug is a rug hand-knottedA rug construction in which the weaver ties each knot of wool or silk pile yarn by hand around adjacent warp threads on a loom, then runs a weft through the row and beats it down. The cut knot ends form the pile, the warps and wefts form the foundation, and the warp ends become the fringe. A rug can take months or even years, and the work leaves subtle irregularities: patterns not perfectly symmetrical, opposite edges a few inches different in length, an uneven fringe. Authentic Persian, Oriental and Turkish rugs are hand-knotted, unlike hand-tufted rugs (sometimes sold as “handmade”) and machine-made ones, whose backs feel stiff and evenly aligned.See in the carpet dictionary in Iran, and the tradition behind it is the oldest documented anywhere. The earliest surviving carpet, the Pazyryk rugThe oldest known pile carpet in the world, woven around the 5th century BC and discovered in 1949 in the frozen tomb of a Scythian noble in Siberia's Altai Mountains. Grave robbers left the burial mound open, so cold and moisture froze the chamber and sealed the carpet in ice for some 2,500 years. Its symmetrical knots, about 36 per square centimeter (roughly 230 per square inch), show that carpet weaving was already a mature art in antiquity. It is often described as the oldest Persian rug and as early evidence of tribal weaving, a craft that began as protection against cold and damp. It is displayed in the Hermitage Museum in St. Petersburg.See in the carpet dictionary, was found preserved in a frozen burial mound and dates to the fifth century BC — roughly 2,500 years ago — and it is already accomplished work, not a beginner's craft. What began as warm, hard-wearing floor coverings for tribal households grew, over those centuries, into the art form that every other rug-weaving country has borrowed from.

Two later chapters shaped what a Persian carpet looks like today. Under the Safavid dynastyThe Persian ruling house that reigned from 1501, beginning with Shah Ismail, into the 1730s, whose court patronage of painting, calligraphy and weaving made this the golden age of Persian rugs. Many museum and top-auction masterpieces come from the era, with Tabriz, Herat, Kashan and Kerman the largest centers. As patterns grew more complex, designers, often miniature painters, became separate from the weavers who worked from their drawings; the large central medallion, curvilinear and geometric layouts and richer flowers and vines became hallmarks, and patterns were standardized for export to Asian and European markets. The Afghan invasion of Isfahan in 1722 interrupted weaving in the main manufacturing centers for several years, though tribes and villages carried on.See in the carpet dictionary, from 1501 to 1732, the court promoted weaving alongside painting and calligraphy, and the workshops of Tabriz, HeratRugs from Herat, a historic city in western Afghanistan that was among the largest rug-producing centers of the Safavid period (16th to early 18th century), alongside Tabriz, Kashan and Kerman. The city also gives its name to the Herati design, a repeated diamond holding a small flower or leaves, with curved leaves at its sides, which is said to have originated there and is still woven in many Persian rugs.See in the carpet dictionary, Kashan and Kerman produced the masterpieces that now sit in museums. This is when the great central medallionA large motif at the center of a rug's field, around which the rest of the design is organized; the large central medallion is said to have been introduced in the Safavid era (16th-17th centuries). Floral medallions, typical of city rugs such as Tabriz, Kashan and Sarouk, are often read as a lotus blossom, and the motif has also been read as mirroring the interior dome of a mosque; geometric ones, often hexagonal or diamond-shaped, mark village and tribal rugs such as Heriz and Zanjan. A medallion may stand alone, come with four corner pieces, be flanked by smaller medallions above and below, or repeat down a runner. Rugs with no central motif are called allover. In a well-made rug the medallion sits at the center and the corners mirror one another, as closely as handwork allows.See in the carpet dictionary appeared, and when designs grew elaborate enough that a separate designer — often a miniature painter — drew the pattern onto a cartoon for the weaver to follow. The second chapter came in the nineteenth century, under the Qajar dynastyThe era of the Qajar dynasty, which ruled Persia in the 19th century and produced the largest rug output in Persian history. Weaving revived after the turbulence of the 1700s that had halted the main manufacturing centers, and exports to Europe and America thrived, with England and Germany the biggest buyers. Newer centers such as Sultanabad and Kashan rose alongside Tabriz and Kerman, and European and American companies set up their own manufacturing hubs in Persia. Rugs from these large factories follow standardized, easily recognized designs, unlike village and tribal rugs, whose weavers still design their own patterns.See in the carpet dictionary, when production reached its historical peak, exports to Europe and America boomed, and the workshop industry whose descendants still weave today took its modern shape.

The trade sorts Persian rugs into three families. City rugs — Tabriz, Kashan, Kerman, Nain, Isfahan — are woven in workshops from a drawn design, carry the highest knot densities and come in the widest range of colors, sizes and patterns. Village rugs such as HerizBold village rugs from the Heriz area of northwestern Iran, near Tabriz, and the best-known of all Persian village rugs. A coarse, tough wool pile on a cotton foundation, usually double-wefted for extra thickness, and a low-to-medium knot density (commonly quoted at about 120 to 170 KPSI, roughly 1,900 to 2,600 per 10 by 10 cm) make them very durable; the wool's strength is traditionally credited to copper-bearing mountain water. The classic design is a large angular medallion with four corner pieces, sometimes an allover layout, in a rust red traditionally credited to copper minerals in the local river, with dark navy and cream. Bakshaish and Serapi, the latter now over a century old, are their older forms.See in the carpet dictionary, BakhtiariColorful rugs of the Bakhtiari, a Zagros Mountains tribe that was nomadic until much of it settled southwest of Isfahan in the 19th century and whose weaving now spreads across more than 200 villages; smaller pieces tend to be tribal work and larger ones come from the region's villages. The foundation is usually cotton under a wool pile from the tribe's own sheep, though some small tribal pieces are wool throughout, and every row is beaten down so hard that the pile ends up dense and long-lasting. The signature layouts are the garden panel design (Khesti, also spelled Kheshti), a grid of framed squares that each show a garden scene meant as a view of paradise, and the medallion-and-corner design with a semi-geometric center medallion. Deep red and dark navy are the usual field colors.See in the carpet dictionary and KarajaVillage rugs from a group of villages in the Azerbaijan region of Iran, at the western edge of the Heriz weaving area and named for the village of Karaja at their center. Wool pile on a cotton foundation (very old pieces may have a wool one), Turkish knot and single weft, so the pile is thinner and softer than the usually double-wefted Heriz, and knot density is low to medium. Two bold geometric medallions with hook-like edges typically alternate down a runner, often on a different ground color with each repeat, and on wide rugs the repeated medallions read as a geometric allover, in orange-reds, blues, creams and browns. Their soft, thin pile and great lengths, some over 20 feet (6 m), make them popular as hallway and stair runners.See in the carpet dictionary sit in between, mostly geometric and largely woven from memory. Tribal rugs — Baluch, TurkomanTribal rugs woven by Turkoman (Turkmen) nomads, whose forebears came from the Afghan and Uzbek region and who later settled in the Turkmen region of Iran. Rows of octagonal guls (“flowers”) cover a deep red, reddish-brown or occasionally cream field, accented in black, blue, green or beige; prayer designs also occur. Foundation and pile are usually wool, said to come from the soft undercoat of Karakul sheep, though a cotton foundation is occasionally used. In older pieces each tribe kept its own gul design, whereas newer rugs freely mix them. Turkoman designs inspired Bokhara and Khal Mohammadi rugs and are the Persian design closest to Baluchi work, which they predate; the low-to-medium pile suits places where doors swing over the rug.See in the carpet dictionary, QashqaiTribal rugs woven by the Qashqai, a nomadic tribe of southwestern Iran that unites Turkic, Arab, Kurdish and Lur groups and has lived in the region since at least the 16th century. Designs come from memory rather than written plans, pairing geometric and medallion layouts, occasionally in a simpler, sparsely detailed form, with animals, plants and household objects, in jewel-tone reds, saffron gold and indigo, often on deep red or dark navy grounds. The thick, hard-weaving wool of the tribe's own flocks is durable yet soft, forming a medium-height, dense pile on a cotton or wool foundation that suits busy areas; compact looms keep sizes small, typically 4 x 6 ft (1.2 x 1.8 m) or 5 x 7 ft (1.5 x 2.1 m) plus runners.See in the carpet dictionary, each named after the people who weave it — are made on small portable looms, so they run smaller, and their bold geometric drawing comes from the weaver's own head rather than from paper.

The design vocabulary draws on a deep stock of motifs: Shah AbbasiA classic Persian floral style named after the Safavid ruler Shah Abbas, which began as a royal court pattern about 400 years ago. Its main features are stylized, feather-like palmette leaves and lotus flowers, the lotus being an ancient symbol of long life, arranged in strict symmetry with scrolling ornament around a central medallion, often a rosette. Early examples favored deep reds and blues, while later rugs in this style often turn to muted neutral tones. The design appears in Kashan, Nain and Tabriz rugs.See in the carpet dictionary palmettes, flowing arabesques, the small repeating Herati patternA classic Persian design built on a diamond repeated across the field, with a small flower or leaves inside each diamond and curved leaves at its sides; the leaves are read as stylized fish, said to circle a lotus. The name comes from Herat, the city in Afghanistan where the design is said to originate; it is also called the fish design, and Mahi means “fish” in Persian. It is one of the three main design families, woven as an allover pattern or around a central medallion with diamonds inside and outside it, and it sometimes appears as a thin border. It is common in Tabriz, Sarouk, Mashhad, Moud, Bijar, Hamadan, Abadeh, Zanjan, Kerman and Kashan rugs.See in the carpet dictionary, medallions, garden and tree-of-life compositions. These combine with regional habits into styles a practised eye can place at a glance, from the bold geometric medallions of Heriz to the fine curvilinear florals of Isfahan.

The classic palette is built on natural dyes: madderThe root of the madder plant (Rubia tinctorum), a natural red dye and the source of the terracotta tones in Persian and Oriental rugs. Together with indigo and walnut husks it is among the plant dyes used to color the wool, bonding to its natural lanolin. Slight shade variations within one color area, known as abrash, are normal in rugs dyed this way.See in the carpet dictionary reds, indigo blues, saffron yellows and soft ivory tones, settled into combinations refined over centuries. Natural dyes age gracefully, mellowing into the patina that older rugs are prized for, and slight shifts of tone between dye batchesA single batch of dye, together with the yarn colored with it, all of which takes the same shade. Natural dyes are made in small artisanal batches, and when one runs out the replacement cannot be matched exactly, so yarn from different lots differs slightly in tone. In a finished rug the difference shows as the color shifts known as abrash, which is read as a sign of hand dyeing, whereas a perfectly flat, uniform color suggests synthetic dyes and machine making.See in the carpet dictionary — the effect called abrashSubtle shifts in color within a handmade rug, often visible as horizontal bands across the field. They arise because successive dye batches never match exactly, because differences in the wool's fat and oil content make colors change unevenly with age, and, in cream areas woven from undyed wool, because the fiber changes tone as it ages. Abrash often grows more distinct with age, so in an older rug it counts as a sign of natural dyes and hand production rather than a fault, while a newer rug is still checked for even color. Machine-made and some new hand-knotted rugs imitate it on purpose.See in the carpet dictionary — are a mark of small-batch natural dyeing, not a flaw.

The pileThe surface of a rug or carpet, made of upright fibers in cut tufts or loops. In a hand-knotted rug it is formed by the cut ends of thousands of wool or silk knots tied onto the warp row by row, trimmed lightly during weaving and given its final height by shearing at finishing. Pile thickness, measured from the back of the rug to the top of the pile, typically runs from low, about 1/8 to 1/4 inch (3 to 6 mm), to high, about 1/2 to 5/8 inch (13 to 16 mm). Fine, dense designs are cut short to keep the pattern sharp; higher pile suits traffic and heavy furniture, lower pile suits door clearance and humid rooms.See in the carpet dictionary is almost always woolA natural animal fiber used for the pile, and in some rugs also the foundation, of high-quality rugs. It is durable, resilient, stain resistant and flame resistant, feels soft and cushioned underfoot, insulates against cold, and takes up dye readily and holds it for many years. It also traps dust particles, which helps reduce allergic reactions. Quality depends above all on where the sheep graze: high-elevation pastures and good feed give thicker, oilier wool, with Manchester, New Zealand and Ghazni wools the best-known prized examples. Early-spring shearing and hand spinning (finer, softer thread than machine spinning) improve it further, while thin, dry wool from dead sheep goes into cheaper rugs.See in the carpet dictionary, and the wool decides much of the rug's quality. The best fleece comes from high-altitude flocks, where it grows thicker and richer in natural oils; spring-sheared wool beats the autumn clip, and hand-spun yarnWool yarn spun from cleaned, carded fleece by hand or on a manual wheel rather than by machine, after which the spun threads are twisted together into thicker, stronger strands before dyeing. It gives finer, softer threads than machine spinning, so the wool feels softer and looks shinier, and hand spinning is said to preserve the wool's natural lanolin. It is usual in Kazak and Peshawar rugs woven in Pakistan and in Afghan Khal Mohammadi rugs, all of which are also colored with natural dyes.See in the carpet dictionary gives a finer, softer thread than machine spinning. Fine pieces add silk highlights to a wool pile, and the finest are woven in pure silk. Foundations are usually cotton in city weaving, wool in tribal and older pieces, silk at the very top of the range.

Every knot is tied by hand, one at a time, in one of two forms: the asymmetric Persian knotThe asymmetrical knot of hand-knotted rugs, the counterpart of the symmetrical Turkish (Ghiordes) knot. The weaver wraps the yarn around one warp thread and passes it under the neighboring one, usually working by hand without a hook. On the back of the rug the knots look staggered or diagonal rather than like tidy squares, and the pile feels softer; the knot permits finer detail and higher knot density. In Iran, a rule of thumb ties it to the central, eastern, and southern rugs (Kashan, Isfahan, Nain, Kerman), while the northwest and west favor the Turkish knot, though exceptions exist. Fine curvilinear florals are often credited to it, but Turkish-knot rugs can be just as intricate.See in the carpet dictionary, usual in central and eastern Iran, or the symmetric Turkish knotOne of the two main knots of hand-knotted rugs, also called the symmetrical knot (the other being the asymmetrical Persian or Senneh knot). The yarn is looped around two adjacent warp threads with both ends emerging between them, so the back shows small, even, squarish knot heads; weavers often tie it with a hook. Named after the town of Ghiordes (modern Gördes) in Turkey, it is typical of Turkey, the Caucasus and northwestern Iran (Tabriz, Bijar, Heriz, village Hamadan), where Seljuk Turks are said to have introduced it, and gives a durable, precise pile. The Persian knot is often credited with finer detail, yet knot type is a tendency, not a limit: Tabriz rugs woven with the Turkish knot reach about 500 knots per square inch (roughly 78 per cm²).See in the carpet dictionary, common in the north-west ever since Seljuk weavers introduced it in the eleventh and twelfth centuries. A large carpet holds in the region of two million knots and can occupy a weaver for about a year.

Knot densityThe number of knots in one square inch of a hand-knotted rug (KPSI; 1 KPSI is about 15.5 knots per 10 x 10 cm), counted on the back with a ruler by multiplying the knots along one inch of height by those along one inch of width, averaged over two or three areas. More knots give sharper detail, like a higher-resolution screen, and, all else equal, somewhat more durability and a higher price, but density alone does not grade quality: Heriz and Bijar are durable at low to medium counts, while floral curvilinear designs blur without enough knots. Figures run from under about 80 for coarse tribal weaves such as Gabbeh and Qashqai, through roughly 120 to 225 for many village rugs and 300 to 700 for fine city rugs such as Nain and Isfahan, to 600 to 1,000 or more for pure silk Qum.See in the carpet dictionary is the figure newcomers fixate on, and the finest silk-foundation pieces do reach as much as 1,000 knots per square inch. But densityA measure of how tightly a carpet is packed. In machine-made carpet it describes the fibers in the pile and is calculated by multiplying the face weight by 36 and dividing by the pile height; higher density generally indicates better durability and performance. In hand-knotted rugs it means knot density (KPSI, knots per square inch), counted on the back and averaged over several areas (150 KPSI is about 23 knots per cm²). Like image resolution, higher density allows finer curves and sharper designs, usually with a lower-trimmed pile and more labor, but it is not the sole measure of quality: bold geometric village rugs are made at low to medium density.See in the carpet dictionary only matters as far as the drawing demands it: a curvilinear Isfahan needs a fine weave to stay sharp, while a geometric Heriz is famously durable at a modest count. Material, symmetry, color harmony and condition say more about quality than any single number.

Persian carpets settle into modern rooms as naturally as classical ones, as a focal point in a living room, a foundation under a dining table or a quieter accent in a bedroom. Care is undemanding: gentle vacuuming without a rotating brush, an occasional turn for even wear, and a professional wash about every five years — sooner in a hallway or entrance, less often in a quiet room.

A hand-knotted Persian rug tends to outlast its owners. Pieces a century old regularly survive in fine condition, their colors settled and their pile supple, often looking better than when they left the loomThe frame on which the warp (vertical) threads are strung first and held under tension so the weft (horizontal) threads can be interlaced through them and the knots tied onto them. Hand-knotted rugs are made on simple looms, from those set up in weavers' homes to the compact, transportable ones of nomadic weavers, where every knot is tied by hand. Loom size sets rug size: nomads' small looms typically yield rugs no larger than about 4 x 6 or 5 x 7 ft (1.2 x 1.8 m or 1.5 x 2.1 m), city workshops with very large looms weave palace sizes, and the number of looms a workshop runs gauges its scale. Wooden looms in tribal and village weaving expand and contract over time, one cause of crooked rugs. Power looms such as Wilton, Axminster, and Jacquard, the industrial descendants, make machine-woven carpet.See in the carpet dictionary. A well-chosen, well-kept rug holds its worth and passes down as a family heirloom rather than being replaced — which is precisely what the knots, the wool and the dyes were always for.