Most probably a ceremonial (?) pole weapon tip based on one of the following, but probably a Fauchard variant:
FauchardA fauchard is a
type of polearm which was used in
medieval Europe from the 11th through the 14th centuries. The design consisted of a curved blade put atop a 6–7-foot long pole. The blade bore a moderate to strong curve along its length, however unlike a glaive the cutting edge was only on the concave
side. This made the fauchard blade resemble that of a sickle or a scythe. This was not a very efficient design for the purposes of war, and was eventually modified to have one or more lance points attached to the back or top of the blade. This weapon is called a fauchard-fork, but is very often erroneously referred to as a guisarme or bill-guisarme since it superficially appears to have a "hook".
GuisarmeA guisarme (sometimes gisarme, giserne or bisarme) was a pole weapon used in Europe primarily between 1000–1400. It was used primarily to dismount knights and horsemen. Like most polearms it was developed by peasants by combining hand
tools with long poles: in this case by putting a pruning hook onto a spear shaft. While hooks are
fine for dismounting horsemen from mounts, they lack the stopping power of a spear especially when dealing with static opponents. While early designs were simply a hook on the end of a long pole, later designs implemented a small
reverse spike on the back of the blade. Eventually weapon makers incorporated the usefulness of the hook in a variety of different polearms and guisarme became a catch-all for any weapon that included a hook on the blade. Ewart Oakeshott has proposed an alternative description of the weapon as a crescent shaped socketed
axe.
refer:
http://en.wikipedia.org/wiki/Pole_weapon