Yet another meaning for ferrule is the sharp point at the base of a ski pole.
They come in various shapes and sizes, depending on the condition of
the snow they're designed for. Powder ferrules are quite broad and blunt,
whereas ferrules designed for icy and packed powder conditions are usually
quite narrow and sharp.
The point of the ferrule is usually made of some kind of metal, varying from
stainless steel to carbide, depending on how much you want to spend.