Used by Jewelers in completing Dwarves of Thorin's Hall reputation quests. Quests can be started at level 39 by talking to NPC Israth, located at the waterfall in the back and West of Thorin's Halls.
Used in recipes for:
Polished Moonstone (requires Superior Workbench)
Dwarf-necklace (requires Superior Workbench, Misty Mountain Silver Ingot (2), Polished Moonstone (1).