The first thing to look at is the warp. These are the threads which run the length of a carpet from the top to the bottom and if you have a complete carpet they probably form the fringe at the top and at the bottom. The warp threads have to be very strong because they take the weight of the carpet when it is on the loom. So they are tightly spun. They are usually not dyed because they are completely concealed by the knotted pile so they are usually undyed cotton which would be white colour or undyed wool which is usually a dark brown. The second thing to look at are the knots,and the knots are tied around the warp threads. Each individual knot is tied around two warp treads,and the weaver will complete one whole row of knots and then insert the third element of the the structure, which are the weft threads, and the weft threads go from side to side across your carpet. In this one it is brown wool and you can see because this is a fragment how its unravelling so here you have the warp threads, the knots and then after every row of knots some shoots of weft are taken across.
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