Dug this up in my grandfathers stuff. The head of the hammer I swear seems like some sort of animal bone??? Maybe a deer I have no idea. It looks to be pretty old too and there is some wear.
"A small mallet with horn head that was described as an early to mid-nineteenth century reflex hammer. It is not a reflex hammer, but it is a dental mallet that was used to hammer rubber and acrylic dentures out of the stone beds of the cuvettes. This type of mallet was in general use until c. 1970" http://www.antiquescientifica.com/mis_id_mid_19th_c._horn_reflex_hammer.jpg