I don't know about historically but that pith in the center of a piece of antler doesn't really polish all that well and it doesn't look too good either. If that tang is long enough you can put some threads on it, run it all the way through the antler, and screw a metal end piece on there. Or, you could take a piece of wood, buffalo horn, or even metal and stick it on the end with pins or screws. Historically
all kinds of things have been done to cover those ends, whatever you can dream up, but leaving it bare isn't too hot unless you're using a crown ....