A Persian wool rugs woven with such a wool can survive 50 years or even more with relatively little wear, provided it’s being cared for properly.
Wool used for making Persian rugs is divided into three categories:
Live wool, known also as as kurk or kork wool, is a fiber that was sheared from a sheep while it was still alive, usually during springtime. Good quality live wool is easy to recognize: it is soft thanks to natural oil, known as lanolin and resilient to elements and external factors such as moisture. Quality of wool has a great impact on how good will the rug look, but also on its price. Dead wool, on the other hand, is removed from a hide of a dead sheep using special chemicals. Although it tends to be cheaper, it’s not a good material for making a carpet, as dead wool is extremely brittle and easy to wear down. It’s color is more clouded than live wools and is very dry to touch. Used wool is salvaged from old clothes or carpets and then re-dyed. It’s quality is similar to dead wool, which makes it a very cheap, but questionable purchase.
Nowadays majority of wool used to make Persian carpets is imported from New Zealand or Merino, due to high demand that local sheep cannot meet. In some cases sheep wool is mixed with camel or goat hair in order to make costs of carpet production lower and more profitable for the weaver.