From “Oriental Rugs – Volume 4 Turkish’ (Zipper & Fritzsche)”:
Turkish carpets, including those from east Anatolia attributed to the Kurds and other ethnic groups, are usually made of wool and tied with the Turkish symmetric knot. They range in size from the ‘yastık’ (pillow) to the large, hall-sized carpet. Provincial and tribal weavings often have uncomplicated patterns, clear colours and a plain texture. The one group of exceptions to this generalised view consists of 19th and 20th century urban factory production from Istanbul, Hereke, Kayseri, etc., which have complex designs of Persian inspiration, often are woven completely or partly in silk and may be Persian (asymmetrically) knotted.

Note that the first four pictures in this sub-gallery open sub-galleries with many more pictures.