This slim antique cotton or thread barrel is carved of real ivory with smooth sides and turned bands. It has a beautiful old patina and ivory grain pattern. The top unscrews from the barrel and inside is a little spool which was to be wrapped with thread. There's a hole in the side to feed the thread through and the knob on top winds in the thread. The condition is excellent with no chips, cracks or other damage.
It would have graced an English workbox of the early 19th century. It measures 1 1/4" high by 5/8" in diameter. Some are shown on p. 44 of Nerylla Taunton's "Antique Needlework Tools and Embroideries" and she also shows the style of workbox it would have been part of.