Silk Carpets made in Kashmir are knotted by hand. Knots per square inch determine the price of a carpet. The pile is almost always silk, the warps and wefts are either cotton or silk. Carpets having cotton warps and wefts are called cotton-silk carpets and are priced lower on the scale. The knottage is low, maximum being 320 knots per square inch. On the other hand, carpets with silk warps and wefts are called silk on silk carpets and are priced the highest on the scale. There have been silk on silk carpets sold with knottage as high as 3000 knots per square inch or more.