To tell the difference between an authentic hand made Persian Rug and machine made is not always easy.  Today, one can find on the market machine made carpets that look a lot like the authentic one, in design, in name and in feel.  

One thing you should know, machines do not make knots.  They put the wool fiber into place and then back them with latex to secure them. This results into a rough to the touch surface. But today, the stores are full with machine made carpets that hold names like “Kashan,Tabriz, Kashmar, etc.” with  designs and colors that match the names.  The softness of these rugs is that of a true Persian or Oriental Rug because, they also use natural wool just as the Persian weaver sometimes uses synthetic fiber to make his rug.  If you ever wonder weather or not the rug you are buying is truly a Persian rug or not, then do the burning test.  Take a small thread out of the carpet and burn it.  If its wool, it will smoke and smell like hair.  If you want to test the quality of the wool, vacuum the back and the front of the carpet and then rub the vacuumed surface with your hand a dozen of times.  Roll the fibers that have shed in your hand.  If they are equal or greater than the thickness of the rug itself, the chances are that the wool is of lower quality.  You see that even the making of an authentic Persian Rug can be of lower quality.

Does the thickness of the rug matter in determining its quality?  Not necessarily.  What is important to know is if the rug is sheered to the proper height when we consider the quality of the wool and the density of the knots.  When the density of the knots is low and the carpet is sheered too low, the design will not look as attractive as one that has higher density and is sheered correctly.  This is where the expertise of the master sheerer is put to test.  Before he starts the sheering process he should evaluate and know exactly how to proceed in order to optimize the characteristics and the design of the carpet.  

It has been said and still the same saying goes that a good quality Persian Rug looks just as clear at the back as it does at the front.  Even though this statement is true, sometimes the technique used to make the knot shows a great deal of weft on the reverse of the rug.  This doesn’t mean that the rug has not been knotted tightly.  There is also another reason why the back doesn’t look as clear as the face of the rug.  Sometimes, the fiber strays from the knot.  After the weaving is finished, the weaver burns the loose strands cleaning the look of the back.  When this method is not used, the back of the carpet has more of a fuzzy and unclear look.  But this doesn’t mean that the carpet has not been woven tightly.

They say that the finer the knots the higher the quality.  This is not always true.  Sometimes a Persian Rug can have high kspi but the wool that is used is of lower quality, shortening the life of the carpet.  

So as we see, higher kspi does not always equate with higher quality.  Higher kspi is only one of the factors of a high quality Persian Rugs.

In conclusion, If you want to make sure that the rug you are buying is an authentic Persian Rug, ask for the certificate of authenticity.  Talk to the sales person.  Ask questions.  Usually in the small stores, the sales man is also the owner.  So his own reputation being on line he will give you the right information about the product you are considering to buy.   Now that you learned a few things about Persian rugs, go out shopping and practice your knowledge.