This weapon is identical to a normal Long Sword in every way (thus still breakable because of the Iron Crisis), except that it is the only sword that will satisfy Hull and his quest. You could keep it and wield it yourself, if you wanted to, or you could sell it to Winthrop for 5 (give or take, depending on your Charisma score) instead of returning it to Hull for a much better reward, if you've got some sort of self-punishing grudge against him.
|“||These swords are usually referred to as double-edged swords, war swords, or military swords. In many cases, the long sword has a single-edged blade. There is no single version of the long sword; the design and length vary from culture to culture and may vary within the same culture depending on the era. Among the most common characteristics of all long swords is their length, which ranges from thirty-five inches to forty-seven inches. In the latter case, the blade is known to take up forty inches of the total length. Most long swords have a double-edged blade and a sharp point at the tip. Despite the tip, the long sword is designed for slashing, not thrusting.||”|