19th century carved bone 3-1/2″ long thread winder

19th century carved bone thread winder made in a less common rectangular shape to hold six colors of silk. From China, very likely made as part of a sewing box for export. 3-1/2″ long by 1-1/2″ wide.

Generally very good condition with some minor chips and rough spots on the notched protrusions. The bone is quite thick (nearly 1/8″) and the carvings are sharp and well detailed.