The Persian carpet (Middle Persian: bōb, Persian: فرش farsh, meaning "to spread"; sometimes قالی qāli) is an essential part of Persian art and culture. Carpet-weaving is undoubtedly one of the most distinguished manifestations of Persian culture and art, and dates back to ancient Persia. In 2008, Iran’s exports of hand-woven carpets was $420 million or 30% of the world's market. There is an estimated population of 1.2 million weavers in Iran producing carpets for domestic markets and international export. Iran exports carpets to more than 100 countries, as hand-woven rugs are one of its main non-oil export items. The country produces about five million square meters of carpets annually—80 percent of which are sold in international markets. In recent times Iranian carpets have come under fierce competition from other countries producing reproductions of the original Iranian designs as well as cheaper substitutes.
The designs of Iranian carpets are copied by weavers from other countries as well. Iran is also the world's largest producer and exporter of handmade carpets, producing three quarters of the world's total output. Though in recent times, this ancient tradition has come under stiff competition from machine-made products. Iran is also the maker of the largest handmade carpet in history, measuring 60,546 square feet (5,624.9 square meter).
Persian carpets can be divided into three groups; Farsh / Qāli (sized anything greater than 6×4 feet), Qālicheh (قالیچه, meaning "small rug", sized 6×4 feet and smaller), and nomadic carpets known as Gelim (گلیم; including زیلو Zilu, meaning "rough carpet"). In this use, Gelim includes both pile rugs and flat weaves (such as kilim and soumak).
The art of carpet weaving existed in Iran in ancient times, according to evidence such as the 2500-year-old Pazyryk carpet, dating back to 500 B.C., during the Achaemenid period. The first documented evidence on the existence of Persian carpets comes from Chinese texts dating back to the Sassanid period (224 – 641 AD). This art underwent many changes in various eras of the Iranian history to an extent that it passed an upward trend before the Islamic era until the Mongol invasion of Persia. After the invasion, the art began to grow again during the Timurid and Ilkhanid dynasties.
With the passage of time, the materials used in carpets, including wool, silk and cotton, will decay. Therefore archaeologists are rarely able to make any particularly useful discoveries during archaeological excavations. What has remained from early times as evidence of carpet-weaving is nothing more than a few pieces of worn-out carpets. Such fragments do not help very much in recognizing the carpet-weaving characteristics of pre-Seljuk period (13th and 14th centuries AD) in Persia.
Zoroastrian period 
In a unique archaeological excavation in 1949, the exceptional Pazyryk carpet was discovered among the ices of Pazyryk Valley, in Altai Mountains in Siberia. The carpet was found in the grave of a Scythian prince. Radiocarbon testing indicated that the Pazyryk carpet was woven in the 5th century BC. This carpet is 283 by 200 cm (approximately 9.3 by 6.5 ft) and has 36 symmetrical knots per cm² (232 per inch²). The advanced weaving technique used in the Pazyryk carpet indicates a long history of evolution and experience in this art. Pazyryk carpet is considered as the oldest carpet in the world. Its central field is a deep red color and it has two wide borders, one depicting deer and the other Persian horsemen.
The Pazyryk carpet was thought, by its discoverer Sergei Rudenko, to be a product of the Achaemenids. Currently, whether it is a nomadic product with Achaemenid influence, or a product of the Achaemenids remains the subject of debate.
Historical records show that the Achaemenian court of Cyrus the Great at Pasargade was decked with magnificent carpets. This was over 2,500 years ago, while Persia was still in a weak alliance with Alexander the Great. Alexander II of Macedonia is said to have been dazzled by the carpets in the tomb area of Cyrus the Great at Pasargade.
By the sixth century, Persian carpets of wool or silk were renowned in court circles throughout the region. The Bahârestân (spring) carpet of Khosrow I was made for the main audience hall of the Sassanid imperial Palace at Ctesiphon in the Sassanid province of Khvârvarân (in present-day Iraq). It was 450 feet (140 m) long and 90 feet (27 m) wide and depicted a formal garden. With the occupation of the Sassanid capital, Tuspawn, in the 7th century CE, the Baharestan carpet was taken by the Arabs, cut into small fragments and divided among the victorious soldiers as booty.
Islamic period 
In the 8th century A.D. Azarbaijan Province was among the largest centers of carpet and rough carpet (ziloo) weaving in Iran. The Province of Tabarestan, besides paying taxes, sent 600 carpets to the courts of caliphs in Baghdad every year. At that time, the main items exported from that region were carpets, and small carpets for saying prayers (also known as prayer mats). Furthermore, the carpets of Khorassan, Sistan and Bukhara, because of their prominent designs and motifs, were in high demand among purchasers. During that era dyeing centers were set up next to carpet weaving looms. The industry began to thrive until the attack on Iran by the Mongol army.
During the reigns of the Seljuq and Ilkhanate dynasties, carpet weaving was still a booming business, and a mosque built by Ghazan Khan in Tabriz, in northwestern Iran, was covered with superb Persian carpets. Sheep were specially bred to produce fine wool for weaving carpets. Carpet designs depicted by miniature paintings belonging to the Timurid era lend proof to the development of this industry at that time. There is also another miniature painting of that time available which depicts the process of carpet weaving. Oriental carpets in Renaissance painting from Europe are often given detailed depictions that help fill in gaps in the record of actual surviving carpets.
The designs share a common style with Persian decoration in other media, such as tilework and non-figurative pages in manuscripts with Persian miniatures. It is thought that the designs for carpets made for the court were made by the court artists and sent to the weavers, and the court commissions led the development of style the used in other works.
The most famous Persian carpet from this period is a large Safavid (1501–1736) example known as the Ardabil Carpet, in the Victoria and Albert Museum in London, which in fact is now a combination of two original carpets, with another piece from the second in Los Angeles. This has been the subject of endless copies ranging in size from small to full scale. There is an 'Ardabil' at 10 Downing Street and even Hitler had an 'Ardabil' in his office in Berlin. The carpets were woven in 1539-40 according to the dated inscriptions. The foundation is of silk and the pile of wool with a knot density of 300-350 knots per square inch ( 465-542 thousand knots per square meters). The original size of both carpets was 34 by 1⁄217 feet (10.5 by 5.3 metres). 1⁄2 Los Angeles County Museum of Art See also Victoria & Albert Museum
There is much variety among classical Persian carpets of the 16th and 17th century. There are numerous sub-regions that contribute distinctive designs to Persian carpets of this period such as Tabriz and Lavar Kerman. Common motifs include scrolling vine networks, arabesques, palmettes, cloud bands, medallions, and overlapping geometric compartments rather than animals and humans. Figural designs are particularly popular in the Iranian market and are not nearly as common in carpets exported to the west.
Modern period 
Although carpet production is now mostly mechanized, traditional hand woven carpets are still widely found all around the world, and usually have higher prices than their machine woven counterparts due to them being an artistic presentation. Iran exported $517 million worth of hand woven carpets in 2002. Iran's carpet exports amounted to US$635 million in 2005, according to the figures from the state-owned Iran Carpet Company. Most are top-notch hand-woven products. In October 2007, National Iranian Carpet Center revealed that hand-woven carpets have ranked first in country's non-oil exports and hold the third position among overall exports. Nearly five million workers are engaged in the Iranian carpet industry, making it one of the biggest enterprises in the country.
In recent times Iranian carpets have come under fierce competition from other countries producing fakes of the original Iranian designs as well as genuine cheaper substitutes. Most of the problems facing this traditional art is due to absence of patenting and branding the products as well as reduced quality of raw materials in the local market and the consistent loss of original design patterns. The absence of modern R&D is causing rapid decline in the size as well as market value of this art.
To give one example, the "Carpet of Wonder" in the Sultan Qaboos Grand Mosque in Muscat in the Sultanate of Oman measures 4,343 square metres. Its construction required four years of labour by 600 workers, resulting in 12 million man hours of work.
Wool is the most common material for carpets but cotton is frequently used for the foundation of city and workshop carpets. There are a wide variety in types of wool used for weaving. Those of which include Kork wool, Manchester wool, and in some cases even camel hair wool. Silk carpets date back to at least the sixteenth century in Sabzevar and the seventeenth century in Kashan and Yazd. Silk carpets are less common than wool carpets since silk is more expensive and less durable; they tend to increase in value with age. Due to their rarity, value and lack of durability, silk carpets are often displayed on the wall like tapestries rather than being used as floor coverings.
Designs, motifs, and patterns 
Persian rugs are made up of a layout and a design which in general included one or a number of motifs. The Iran Carpet Company, a specialist in the subject, has attempted to classify Persian carpet designs and has carried out studies of thousands of rugs. Their results show that there have been slight alterations and improvements to almost all original designs. In its classification the company has called the original designs as the 'main pattern' and the derivatives as the 'sub patterns'. They have identified 19 groups, including: historic monuments and Islamic buildings, Shah Abbassi patterns, spiral patterns, all-over patterns, derivative patterns, interconnected patterns, paisley patterns, tree patterns, Turkoman patterns, hunting ground patterns, panel patterns, European flower patterns, vase patterns, intertwined fish patterns, Mehrab patterns, striped patterns, geometric patterns, tribal patterns, and composites.
Design can be described in terms of the manner in which it organizes the field of the rug. One basic design may serve the entire field, or the surface may be covered by a pattern of repeating figures. In areas using long-established local designs, the weaver often works from memory, with the patterns passed on within the family. This is usually sufficient for simple rectilinear design. For the more elaborate curvilinear designs, the patterns are carefully drawn to scale in the proper colours on graph paper. Each square thus becomes a knot, which allows for an accurate rendition of even the most complex design. Designs have changed little through centuries of weaving. Today computers are used in the production of scale drawings for the weavers.
Persian rugs are typically designed using one of four patterns: all-over, central medallion, compartment and one-sided. Some abstract asymmetrical design can be found but most of these can be described as one-sided or unidirectional.
There are a number of patterns which are found in Persian and Oriental rugs called 'motifs', these designs have different meanings and tend to be used depending on the area the rug was woven although it is not unusual to find more than one motif in a single rug.
Some of the more common motifs are:
Techniques and structures 
Long weaving process 
The weaving of pile rugs is a difficult and tedious process which, depending on the quality and size of the rug, may take anywhere from a few months to several years to complete.
To begin making a rug, one needs a foundation consisting of warps: strong, thick threads of cotton, wool or silk which run the length of the rug and wefts similar threads which pass under and over the warps from one side to the other. The warps on either side of the rug are normally combined into one or more cables of varying thickness that are overcast to form the selvedge.
Weaving normally begins by passing a number of wefts through the bottom warp to form a base to start from. Loosely piled knots of dyed wool or silk are then tied around consecutive sets of adjacent warps to create the intricate patterns in the rug. As more rows are tied to the foundation, these knots become the pile of the rug. Between each row of knots, one or more shots of weft are passed to tightly pack down and secure the rows.
When the rug is completed, the warp ends form the fringes that may be weft-faced, braided, tasseled, or secured in some other manner.
Looms do not vary greatly in essential details, but they do vary in size and sophistication. The main technical requirement of the loom is to provide the correct tension and the means of dividing the warps into alternate sets of leaves. A shedding device allows the weaver to pass wefts through crossed and uncrossed warps, instead of laboriously threading the weft in and out of the warps.
Horizontal looms 
The simplest form of loom is a horizontal; one that can be staked to the ground or supported by sidepieces on the ground. The necessary tension can be obtained through the use of wedges. This style of loom is ideal for nomadic people as it can be assembled or dismantled and is easily transportable. Rugs produced on horizontal looms are generally fairly small and the weave quality is inferior to those rugs made on a professional standing loom.
Vertical looms 
Vertical looms are undoubtedly more comfortable to operate. These are found more in city weavers and sedentary peoples because they are hard to dismantle and transport. There is no limit to the length of the carpet that can be woven on a vertical loom and there is no restriction to its width.
There are three broad groups of vertical looms, all of which can be modified in a number of ways: the fixed village loom, the Tabriz or Bunyan loom, and the roller beam loom. The fixed village loom is used mainly in Iran and consists of a fixed upper beam and a moveable lower or cloth beam which slots into two sidepieces. The correct tension is created by driving wedges into the slots. The weavers work on an adjustable plank which is raised as the work progresses.
The Tabriz loom, named after the city of Tabriz, is used in North Western Iran. The warps are continuous and pass around behind the loom. Tension is obtained with wedges. The weavers sit on a fixed seat and when a portion of the carpet has been completed, the tension is released and the carpet is pulled down and rolled around the back of the loom. This process continues until the rug is completed, when the warps are severed and the carpet is taken off the loom.
The roller beam loom is a traditional Turkish village loom, but is also found in Iran and India. It consists of two movable beams to which the warps are attached. Both beams are fitted with ratchets or similar locking devices and completed work is rolled on to the lower beam. It is possible to weave very long rugs by these means, and in some areas of Turkey rugs are woven in series.
In order to operate the loom, the weaver needs a number of essential tools: a knife for cutting the yarn as the knots are tied; a comb-like instrument for packing down the wefts; and a pair of shears for trimming the pile. In Tabriz the knife is combined with a hook to tie the knots which lets the weavers produce very fine rugs, as their fingers alone are too thick to do the job.
A small steel comb is sometimes used to comb out the yarn after each row of knots is completed. This both tightens the weave and clarifies the design.
A variety of instruments are used for packing the weft. Some weaving areas in Iran known for producing very fine pieces use additional tools. In Kerman, a saber like instrument is used horizontally inside the shed, and in Bijar a heavy nail-like tool is used. Bijar is also famous for their wet loom technique, which consists of wetting the warp, weft, and yarn with water throughout the weaving process to make the elements thinner and finer. This allows for tighter weaving. When the rug is complete and dried, the wool and cotton expand to make the rug incredibly dense and strong.
A number of different tools may be used to shear the wool depending on how the rug is trimmed as the rug progresses or when it is complete. Often in Chinese rugs the yarn is trimmed after completion and the trimming is slanted where the color changes, giving an embossed three-dimensional effect.
Two basic knots are used in most Persian Carpets and Oriental rugs: the symmetrical Turkish or Ghiordes knot (used in Turkey, the Caucasus, East Turkmenistan, and some Turkish and Kurdish areas of Iran), and the asymmetrical Persian or Senneh knot (Iran, India, Turkey, Pakistan, China, and Egypt).
To make a Turkish knot, the yarn is passed between two adjacent warps, brought back under one, wrapped around both forming a collar, then pulled through the center so that both ends emerge between the warps.
The Persian knot is used for finer rugs. The yarn is wrapped around only one warp, then passed behind the adjacent warp so that it divides the two ends of the yarn. The Persian knot may open on the left or the right, and rugs woven with this knot are generally more accurate and symmetrical.
Other knots include the Spanish knot looped around single alternate warps so the ends are brought out on either side and the Jufti knot which is tied around four warps instead.
Flat-woven carpets 
Flat woven carpets are given their colour and pattern from the weft which is tightly intertwined with the warp. Rather than an actual pile, the foundation of these rugs gives them their design. The weft is woven between the warp until a new colour is needed, it is then looped back and knotted before a new colour is implemented.
The most popular of flat-weaves is called the Kilim. Kilim rugs (along with jewellery, clothing and animals) are important for the identity and wealth of nomadic tribes-people. In their traditional setting Kilims are used as floor and wall coverings, horse-saddles, storage bags, bedding and cushion covers.
Various forms of flat-weaves exist including: