The word qiviut (plural) or qiviuq (singular) refers to the inner wool, or undercoat, of the muskox. (The word is pronounced kee-vee-ute.) In Inuktitut, one of the principal indigenous Inuit languages of Canada, the same word is also occasionally used to refer to the downy under-feathers of birds.

More closely related to sheep and goats than to cattle or bison, the muskox is not an ox, nor does it produce musk. What it does have, is a two-layered coat, and “qiviut” refers specifically to the soft underwool beneath the longer outer, or guard, layer. Unlike sheep, musk oxen are not sheared. Qiviut is shed naturally each spring. In the wild, it can be gathered where it falls to the ground or catches on trees, fences, or shrubs. On the farm, this valuable fiber is gently combed out over several sessions. Like cashmere, qiviut needs to be separated from the stiffer outer guard hairs, either by hand or machine, before it can be used.

Qiviut wool is highly prized, as it has qualities not found in the wool of other animals. It is stronger and warmer than sheep’s wool, and softer than cashmere. Unlike sheep's wool, it does not shrink in water at any temperature; this means it cannot be used to make felt. However, it can be, and is, commonly used for hats and scarves. Items made from it can be very expensive; a high quality knitted scarf can cost over $300 U.S (252.6 EUR) but, on the plus side, can last over 20 years with proper care.

More Info: en.m.wikipedia.org