Antler is a lot of work to split, but much easier than I first thought when venturing into those realms. Remember throughout the process that using water eases the process a lot, that includes the splitting. Below: The wedge (on top), the split piece, and the antler hammer.
First you need to score or saw around the tine into the core. Breaking it off is then easily accomplished by putting stress on the point where you have sawed.
You can either free the piece in both ends first or just one end and then start scoring the paralell grooves.
Photo: Sawed off and have started to groove the lenghts.
Score or drill a little depression to take the wedge.
If you split the piece into three or more, a round wedge is best suited to accomplish the splitting. That can just be a regular tine. If the piece is only split in two like this one, you are better off with a flat one, but such a piece is hard to find unless you already have split a piece before. So you may either have to get by with a round one or one made from hardwood.