Shahtoosh (from Persian شاهتوش 'king of wools'), also known as Shatoush, is a wool obtained from the fur of the chiru (Pantholops hodgsonii, also called Tibetan antelope). Also, shawls made from the wool of the chiru are called shahtoosh. Shahtoosh is the finest animal wool, followed by vicuña wool. As undomesticated wild animals, the chirus cannot be shorn, so they are killed for this purpose. Due to the severe decline of the chiru population by 90 % in the second half of the 20th century, they were internationally classified as a critically endangered species until 2016. Since 2016, they have been classified as a near threatened species due to species conservation programs and partial recovery of population size. The wool is mostly used to make luxurious scarves and shawls, although the production, sale, and acquisition of shahtoosh has been illegal under CITES since 1979. On the black market, shahtoosh shawls fetch prices ranging from $5,000 to $20,000. Properties The average fiber diameter of the down hair is 11.45 microns with a standard deviation of 1.78 microns and a coefficient of variation of 15.55 %, and a span from 6.25 to 16.25 microns. Because of the small fiber diameter, the down hair of the chirus is the finest of all animal hairs. The down hair is wavy and mosaic scaled with a scale spacing of 5.3 scales per 100 microns. The scale width tapers in the upward direction of the hair to the next scale ring. At the scale edge, the hair is thicker, making the fiber diameter uneven along the length of the hair. The hair of the chirus is beige to gray, and white on the belly. Only 12-14 % of the down hair is white and more expensive. The lighter the hair color, the lighter shades can be dyed. The guard hairs are separated from the down hair by sorting. However, due to the fineness and low tensile strength of the fiber, sorting can only be done manually and incompletely, resulting in guard hairs in scarves. Due to tiny air bubbles in the hair, the guard hairs of shatoosh show a pattern like laid stone slabs under a light microscope. This allows shatoosh to be distinguished from cashmere wool products under a light microscope, where guard hairs of cashmere wool look like dark stripes with light-colored edges. Use The animals, which live wild in the Changtang region, Xinjiang