Created in Germany ~1500-1525, this ivory carving is the terminal on a rosary.
Each bead of the rosary represents the bust of a well-fed burgher or maiden on one side, and a skeleton on the other. The terminals, even more graphically, show the head of a deceased man, with half the image eaten away from decay.
The other terminal and six exquisitely-carved beads and their silver, partially-gilded mounts, can be seen at the Metropolitan Museum of Art link.
Link, via La Muse Verte.