Astrakhan, broadtail, caracul, and similar fine-fur lamb skins are excluded because they are valued primarily as furskins rather than as leather raw material. They are classified in Chapter 43, which covers furskins and artificial fur, rather than Chapter 41. The distinction rests on the character of the wool or fur and the trade use of the skin.

Pickling involves immersing the dehaired skin in an acid-salt solution, which partially prepares it for tanning and is a recognized preservation method in the leather trade. 'Otherwise preserved' skins (410229) are those preserved by other means—such as drying or wet-salting—but not pickled and not yet tanned. The preservation method affects the skin's condition on arrival and the subsequent tanning process, and it is the criterion the HS uses to split these two subheadings.