Ghost Ship in a Bottle

Locations:
Price: N/A (Reward from the 'Ghost Ship in a Bottle' quest)
Sellback: 2,500 Gold
Rarity: Unknown Weird Rarity
Base Level: 5
Base Damage: 56-56 30-30
Description: …but how did the ghost get in there?
Thanks to Beowolve, IM_HORRIBAD, Vamparagon and Xia.