These rugs are most commonly a deep shade with a repeating pattern of octagonal "guls", which is also known as an elephant's foot. The shapes and colors of guls varied from one tribe to another and the differences were traditionally used to identify the source of the rug. Wool is generally used as the foundation material, and the wool pile is most commonly tied with Persian knots and is clipped short. The pile is higher, the wool is soft, and the foundation is usually cotton in Pakistan and Indian Bokharas [ref. Lesniak]
Placing the correct size rug in your space is as important as choosing the right color or pattern. A rug that it is too small will shift the balance of the room unfavorably. A rug that is too big, especially in open floor plans, may put the area designations off. There are a few rules of thumb, but a picture says it better. Use these handy guides by Interior Designer Lisa Ferguson to make the best choice.