This is marked as having slashing damage. I can equip it as a conjuror, and when I am in combat, I get crushing damage skill ups. If I turn off my ascension stance (Elemental Avatar), the log shows "You flurry training dummy for x slashing damage" and no longer get any skill ups. Since conjuror's aren't supposed to be able to use slashing weapons, this is rather odd indeed. So. I'm presuming this is supposed to be strictly a crushing weapon so all classes can wield it and it's a display issue.