Khorium Vein
This object can be found in Nagrand (7), Zangarmarsh (6), Isle of Quel'Danas (6), Blade's Edge Mountains (4), Terokkar Forest (4), Netherstorm (4), Shadowmoon Valley (3), Hellfire Peninsula (2), Auchindoun: Sethekk Halls (1) and Coilfang: The Underbog (1).