It is a huge item, mainly made of steel.
It is a type of lance, capable of doing pierce damage.
It could be wielded in mounted combat, but not on foot, its effectiveness dependent on your Polearms skill.
It could be wielded with either one or two hands as an improvised melee weapon.
It feels clumsy, and you figure you could get up to 1 strike per attack with it.
It would be extremely difficult to parry with.
So I'm seeing it's both a Polearm and an Improvised melee weapon. This isn't correct, it it?