This nice little antique piece is engraved with patterns of Madras work dots and circles around the sides. It's a form of scrimshaw work where black lacquer is flowed into the engraved designs. It's carved of real ivory and has a lovely mellow patina and ivory grain.
It has a little rubbing but the overall condition is excellent with no chips or cracks. It measures 3 1/4" long and screws together securely. It's English and dates to the early 19th century. A variety of Madras work needlework tools are shown on p. 87 of Nerylla Taunton's book Antique Needlework Tools and Embroideries.