ArakRugs from Arak, a city in central Iran formerly called Sultanabad, and the villages around it, a weaving region that grew in the Qajar era when exports of Persian rugs to Europe and America thrived. Rug texts also use the city as a reference point: the town of Sarouk lies about 50 km (31 miles) to its north, and the Malayer villages lie between Arak and Hamadan. Older pieces of the area are still sold under the old name Sultanabad.See in the carpet dictionary sits in central Iran, roughly 250 kilometres south-west of Tehran, on the eastern flank of the Zagros. It is the capital of Markazi province, whose name simply means central. The town was founded at the start of the 19th century as a Qajar garrison called Soltanabad, and kept that name until the 1930s, when it was renamed Arak. Around it lies a ring of weaving settlements: the Farahan district and the village of 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 to the north, Mohajeran a short way out of the city, Lilihan to the south. West of all of them the district shades into the Malayer and Hamadan looms, and that is where the confusion over names begins.

Buyers rarely meet the word Arak on a label, and that is the first thing to understand about the region. Its output reaches the market under village and trade names instead: Sarouk above all, then SultanabadAntique Persian carpets from Sultanabad, the former name of the Arak region of Iran, a newer weaving center that flourished under the Qajars in the late 19th and early 20th centuries and supplied European and American buyers. Their typical layout is an allover field of oversized palmettes, lotus blossoms, floral sprays and angular vines, recalling the Shah Abbasi pattern in a rustic village manner rather than the precise curvilinear drawing of city rugs. Indigo or midnight blue with rust or brick red, gold and olive is a classic palette. Because Sultanabad no longer exists under that name, antique examples are scarce and command higher prices.See in the carpet dictionary, Mahal and Ziegler MahalA type of Persian carpet first made in the late 19th century for the European market by the firm Ziegler & Co., with enlarged, modified traditional Persian designs in softer, muted colors suited to Western tastes. A Ziegler Mahal design marks a particular period of production, yet old Ziegler patterns are still reproduced today, so design alone cannot date a rug. The name is also one of several trade names, alongside Oushak, Peshawar, Chobi and Farahan, used for workshop rugs made in Pakistan since roughly the 1970s in traditional Persian and Turkish designs, with a wool pile on a cotton foundation; which name applies varies with design and knot density.See in the carpet dictionary, Farahan, Lilihan, and the Mohajeran or American SaroukA type of Sarouk woven mainly in the 1920s and 1930s, with patterns and colors adapted to what international buyers, above all in the United States, appreciated, and very popular there. It is also known as Mohajeran Sarouk. Its floral design later served as a model for newer Malayer and Mehraban rugs.See in the carpet dictionary. Sarouk itself is a small place about 50 kilometres north of the city, yet the trade stretched the name across the whole district so thoroughly that it is often said in Iran there is no Sarouk town at all, only Arak. Both accounts are true in their own way, and both are worth knowing.

Weaving here was old, but what made the district famous was money from outside. Soltanabad emerged under the Qajars as one of the newer weaving centers, and through the 19th century British and German buying pushed the growth of factories there, alongside Tabriz, Kerman and Mashhad. European and American firms came into Persia in the same period and set up production of their own, weaving for export rather than for local use. That arrangement, with looms organized on a commercial scale around an agent's drawings and dye recipes, is the reason so many large, evenly drawn antique carpets of the period come from this one district.

Sarouk earned its reputation in the same century for careful drawing, rich color and consistent quality, and as exports grew the designs and palettes were adjusted to foreign taste. The clearest case is the Mohajeran or American Sarouk of the 1920s and 1930s, which became very popular in the United States; a deep burgundy Sarouk from that period has usually been re-dyed after weaving to suit Western rooms. Quality dipped briefly in the middle of the 20th century, something the district's master weavers noticed and pulled back up quickly.

Design at the Sarouk end of the district is floral rather than geometric, and semi-formal rather than strictly courtly. 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 allover layouts both occur, with floral allover and floral medallionA floral rug built around one central medallion, either a single large flower or a cluster of small blooms joined into one shape, often echoed by smaller medallions above, below and beside it. The medallion is traditionally said to stand for the sacred lotus. Because it takes up field space, the flowers and branches are smaller and thinner than in allover floral rugs. The design is typical of Tabriz, Kerman, Sarouk and Kashan, and its strong center makes it a natural focal point of a room.See in the carpet dictionary the most common; herati and botehA teardrop-shaped motif with a curved upper tip, ubiquitous in Persian and Kashmiri weaving for centuries. The Persian word is glossed as “budding flower or plant,” and the motif stands for growth and regeneration; it is also read as a cypress that bends in the wind but rarely breaks, a flame, a seed, a pine cone or a stylized almond. When Scottish mills began imitating Kashmir shawls in the 19th century, the boteh became known in the West as “paisley,” after the town of Paisley. In rugs it usually repeats throughout the field, notably in Tabriz, Sarouk, Kerman, Mashhad and Malayer pieces.See in the carpet dictionary appear regularly, and pictorial pieces exist, though far fewer than at Tabriz. One habit is worth memorizing: the main border is usually accompanied by a much thinner secondary borderA narrow band running alongside the wide main border of a rug, framing it and completing the boundary around the field much as a frame surrounds a painting; it is also called a secondary border. Many Sarouk rugs, for example, wrap a much thinner secondary border around the primary one, and wide floral borders, as on some Tabriz and Kashan rugs, are often edged by narrow guards. The broad main border and its slim guards together form a hierarchy of bands that sets off the design.See in the carpet dictionary running alongside it. A vintage example might carry an ivory field of afshan, meaning scattered flowers, with leafy branches, rosettes and paired sprays and no central medallion at all.

At the older Sultanabad and Mahal end the drawing changes character. Allover is the hallmark there as well, but the field fills with oversized palmettes, stylized lotus blossoms, angular vine scrolls and rosettes, each motif slightly varied because it was drawn by hand rather than copied exactly. The effect is a rhythmic, herati-inspired lattice that borrows the 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 vocabulary of Safavid court carpets and rebuilds it with village directness. Where a city rug is precise and curvilinear, an antique Sultanabad reads as bold and architectural, its symmetry strong rather than delicate.

Color is where the region is easiest to recognize. Sarouk fields run to beige, ivory and cream, to dark navy and blue, and to red, with highlights in yellow, several blues and green, drawn from natural dyes that settle into a harmonious whole and improve with age. The most useful test is the red itself: a characteristic Sarouk red leans orange or rust rather than burgundy or scarlet, and the border is usually a different color from the field. Antique Sultanabads go deeper, with indigo grounds, brick red, gold and olive inside a terracotta border.

Construction follows city practice. The foundation is cotton, rigid and stable, which is what keeps large pieces flat and square, and 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 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, occasionally with silk used for highlights. The knot is normally 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, but older Sarouks are regularly found with the symmetrical 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, which is a useful hint at age on a piece with nothing else to date it. Wool quality is the district's other signature: soft, dense and plush underfoot, with the better antiques using fine cork woolA fine, soft grade of wool taken from the neck and inner fleece layer of young sheep, often from the first shearing. Oily with natural lanolin, it feels soft and resilient and gives colors extra shine. It is used for the pile of many fine city rugs from Isfahan, Kerman, Qum, Tabriz, and Mashad, and older antique Sarouks cut to a short pile use it too. Also spelled cork or kurk wool.See in the carpet dictionary.

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 runs from medium to high, reaching roughly 320 knots per square inch (KPSI) at the upper end of Sarouk weaving. Two measured pieces show the spread honestly: a vintage ivory afshan Sarouk of about 3 by 4 metres counted 225 KPSI, fine enough to carry curved floral drawing without stiffness, while an antique Sultanabad of about 3.2 by 4.9 metres counted 116, which gives a sturdy, substantial handle instead. Pile is mostly medium to thick, though some older Sarouks were clipped short over that fine cork wool.

Formats cover the whole ladder. Small mats from about 0.6 by 0.9 metres up to 1.2 by 1.8, medium pieces around 1.5 by 2.1 and 1.8 by 2.7, large carpets from 2.4 by 3 up to 3 by 4.3 metres, and oversize beyond that; the workshops here have long looms and the resources for commissioned palace sizes larger than 3.7 by 5.5 metres. Runners are woven from roughly 1.8 to 6 metres in both narrow and wide widths, and a wide Sarouk runner is usually semi-antique or antique. Small Sarouks also tend to be finely knotted.

In use, these are practical carpets rather than fragile ones. The darker grounds common in the district hide the marks that dining rooms, kitchens and entrance halls inflict, and the soft, deep wool makes them pleasant on stairs, in hallways and in bedrooms where a rug is walked on barefoot. Larger Sultanabad and Mahal pieces, built coarser and heavier, take traffic particularly well. Handle is worth checking alongside pattern, since a short-clipped antique Sarouk in cork wool feels quite different underfoot from a thick modern one.

Three details help place a piece. The state-owned Iran Carpet CompanyA very large government-owned Iranian rug producer, known by the initials ICC and in the United States as the Iranian Rug Company, whose roots reach back to 1934. It runs a network of workshops in about 44 cities, including Tabriz, Hamadan and Sarouk, with some 25,000 workers, and turns out roughly 50,000 square meters (about 540,000 square feet) of rugs a year. It supplies wool and materials and lends money for replacing old looms. Dyeing and weaving are tightly controlled, and even a small flaw has to be unpicked and redone, so its signature signals consistent, high quality whichever town the rug comes from.See in the carpet dictionary ran quality-control workshops in the weaving cities, Sarouk especially, checking materials, color and weaving, and obliging a weaver to cut out and repeat even a small mistake; those rugs took longer to make and stand apart from ordinary district work. The drawing here also travelled: the finest Malayer rugs, woven between Arak and Hamadan, follow Sarouk and Farahan patterns so closely they can be hard to separate, while newer Mehraban work leans on American Sarouk. And Ziegler Mahal patterns are still in production, so design alone never dates a carpet.

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.