You have to make it to the 7 ghosts inside of Blackrock Depths. Talk to one of the ghosts to your right when you enter the room, he will have a chat bubble option that spawns a chalice. Then you place 10 Truesilver Bars, 20 Gold Bars, and some amount of one other thing that I forget right now.. probably 10 or 15 or 20 thorium or dark iron.. into his chalice and he teaches you how to smelt dark iron.
Dark iron bars and items can only be made at the forge inside of Blackrock Depths that Lord Incendius guards.
Edited, Mon Jan 10 02:48:28 2005 by JAEFo