Thus the carpets produced became typical of the Indian origin and gradually the industry began to diversify and spread all over the subcontinent. During the Mughal period, the carpets made on the Indian subcontinent became so famous that demand for them spread abroad. These carpets had distinctive designs and boasted a high density of knots. Carpets made for the Mughal emperors, including Jahangir and Shah Jahan, were of the finest quality. Under Shah Jahans reign, Mughal carpet weaving took on a new aesthetic and entered its classical phase. The Indian carpets are well known for their designs with attention to detail and presentation of realistic attributes.
The carpet industry in India flourished more in its northern part with major centers found in Kashmir, Jaipur, Agra and Bhadohi. Indian carpets are known for their high density of knotting. Hand-knotted carpets are a speciality and widely in demand in the West. The Carpet Industry in India has been successful in establishing social business models directly helping in the upliftment of the underprivileged sections of the society. Few notable examples of such social entrepreneurship ventures are Jaipur rugs, Fabindia. Another category of Indian rugs which, though quite popular in most of the western countries, have not received much press is hand-woven rugs of Khairabad (Citapore rugs). Khairabad small town in Citapore (now spelled as Sitapur) district of India had been ruled by Raja Mehmoodabad.
Khairabad (Mehmoodabad Estate) was part of Oudh province which had been ruled by shii Muslims having Persian linkages. Citapore rugs made in Khairabad and neighbouring areas are all hand-woven and distinct from tufted and knotted rugs. Flat weave is the basic weaving technique of Citapore rugs and generally cotton is the main weaving material here but jute, rayon and chenille are also popular. Ikea and Agocha have been major buyers of rugs from this area.
(Ref : Wikipedia : http://en.wikipedia.org/wiki/Carpet)
Knot density is a traditional measure for quality of handmade carpets. It refers to the number of knots per unit of surface area typically either per square inch or per square centimeter. Number of knots per unit area is directly proportional to the quality of carpet. For two carpets of the same age, origin, condition and design, the one with the higher number of knots will be the more valuable. Knot density is normally measured in knots per square inch (KPSI) which is simply the number of vertical knots across one inch of carpet multiplied by the number of horizontal knots in the same area. Average knot density varies between region and design. A rug could have a knot density half that of another yet still be more valuable, KPSI is only one measurement of quality and value in Persian Carpets. Hand-tying of knots is a very labour-intensive task. An average weaver can tie almost 10,000 knots per day. More difficult patterns with an above-average knot density can only be woven by a skilful weaver, thus increasing the production costs even more
(Ref : Wikipedia : http://en.wikipedia.org/wiki/Knot_density)
On a knotted pile carpet (formally, a supplementary weft cut-loop pile carpet), the structural weft threads alternate with a supplementary weft that rises at right angles to the surface of the weave. This supplementary weft is attached to the warp by one of three knot types (see below), such as shag which was popular in the 1970s, to form the pile or nap of the carpet. Knotting by hand is most prevalent in oriental rugs and carpets. Kashmir carpets are also hand-knotted.
Persian silk rugs are the most intricate, and often most valuable, of all hand-knotted rugs. The fine yet strong silk fibres used in these rugs allow more knots per square inch to be tied giving a clearer image with more detail and increased likeness to real-life, much like an HD TV. Many Persian & Oriental rugs have silk details such as rugs woven in Nain, often the white areas in fine rugs use silk details to give them a sheen and different dimension. Other rugs are wool based on a silk foundation which gives the rug strength yet flexibility while allowing for tighter, more accurate knotting. Some rugs, particularly those from Kashmir and Jaipur can be made from silk on a cotton foundation, these tend to be larger pieces with lower knot counts, the idea that a person can have a large rug made from silk without the need to spend tens of thousands of pounds. These rugs will tent to have a knot-count similar to a wool on cotton rug meaning it will take the same time to weave, the additional costs are only made from the more expensive materials used.
Full silk rugs are the most expensive on the market. Not only are the materials used in making the rug costly but the nature of a 100% silk rug means that more often than not the design is particularly intricate; this means more time is spent weaving a silk rug than a wool rug of similar size. A typical high quality Persian or Oriental rug made in wool might have between 140 and 200 knots per square inch a high quality silk could range between 360 and 650 KPSI thats 2-3 times the number of knots and 2-3 times the amount of work which becomes more skilled the more intricate the pattern becomes; meaning at least 2-3 times the price! The finest silk rugs can have more than 1,000 knots per square inch but are extremely rare and cost in the tens, if not hundreds of thousands of thousands. There are a few things to note when buying a silk rug.
Firstly, many untrustworthy dealers, particularly abroad, sell art-silk rugs claiming them to be silk. Be careful to use reputable dealers. Art-silk which is synthetic materials such as Rayon (cellulose), is not bad in itself, the material gives a soft luxurious feel similar to silk and offers good stain resistance. Some of our Jaldar rugs use Rayon mixed with wool to give a silky feel and appearance. But to claim an art-silk rug is real silk is misleading and unethical at best An extreme example of this is a customer who came into our store with 3 silk rugs for cleaning. One of these was a high quality 575 KPSI Chinese silk; another was a Chinese dragon rug made with what appeared to be mercerized bamboo silk fibre similar to rayon; while the third was a synthetic viscose rayon fibre. One customer with three rugs they believed were silk but only one silk rug.
Another important factor is the level of traffic a silk rug has to put up with. You do not want your intricate masterpiece to be destroyed by heavy foot-traffic and many people hang silk rugs on the wall or keep them in formal rooms that do not get heavy use. Another downside to art-silk is the textile strength while wool is extremely strong and robust (folding on itself 20,000 times before breaking) and silk not as strong but still reliable at 8,000 folds; rayon breaks at just 1000 and often a lot less for lower quality grades. While silk rugs do not have the same strength as wool they are less susceptible to rot, hence many of the worlds oldest rugs are silk. Quality silk rugs are robust pieces but cleaning should only be carried out by a professional. This brings up another problem with many art-silk rayon rugs, there are many horror stories of heavy dye running in synthetic rayon carpets during washing.
Unfortunately many people do not know their silk carpet is in fact art-silk until after this happens. It is difficult to wash a silk rug but even more so for an art-silk replica. While it is possible to carefully clean your own wool rug, doing so with a silk rug is definitely not recommended. We would recommend you to consider the planned usage and maintenance involved before purchasing a silk rug. There are a number of tests for silk with varying levels of usefulness. The rub test suggests rubbing the rug to see if it heats up or not, a silk rug should feel warm whereas a art-silk will remain cool personally we do not find this test very useful or accurate. Another method is the burn test, get a small strand of fabric and hold it with tweezers and attempt to burn it. A silk rug, because it is made of protein (the same as hair) will smell like burnt hair (or more accurately feathers, sometimes charred meat) and will ball up when on fire, the ash should be crispy.
A rayon or art-silk fabric will smell of burnt paper or wood (most paper is made from cellulose) and the ash will be softer and chalky. Many fine wools can often be mistaken for silk which creates a problem as both smell of hair when burnt due to their protein content, wool however is more difficult to set on fire than silk. The most accurate method of testing for silk is to immerse it in a chemical test solution guidance on this can be found online. With these factors in mind make your decision whether you want to go for the most intricate of rugs. Up until 2009 the worlds most expensive rug sold at public auction was a 300 year old Isfahan silk rug which fetched $4.5m in New York (2008). Silk rugs are an excellent choice if they are to sustain light traffic and the budget is permitting.