Kolinsky hair refers to the fine, soft fur obtained from the tail of the Kolinsky, a type of weasel found primarily in Asia. This hair is highly prized for its exceptional quality, durability, and ability to hold a fine point, making it a popular choice for artists and craftsmen, particularly in the creation of high-end paintbrushes. Due to its rarity and the specific conditions required for harvesting, Kolinsky hair is often more expensive than other types of brush hair. It is especially favored by watercolor artists for its ability to retain water and pigment, allowing for smooth and precise application.