Metal pointed tool with bone handle that screws into bone cover. Probably a cataract needle from the first half of the nineteenth century. The '3' on the cover indicates that it was one in a set of opthalmologic instruments, which were standardized by the late eighteenth century (compare to this set from the second half of the nineteenth century:
http://www.museumboerhaave.nl/object/oogheelkundige-instrumenten-in-kist-v25660/), while the grooves in the cover and handle suggest that it was made before Lister discovered the importance of sterile instruments, so first half of nineteenth century.