I found it! I went out in the late morning in search of my pack, and I found it! The thing was filled to the brim with a freshly-mined substance and some books. That would explain why I went all the way out there... in the middle of the woods. There's a cave close by, and from the looks of it, there's a lot of interesting things to be found inside. I don't even know what this stuff is. It's jet black and cold to the touch, but harder than rock. No, really. A rock broke when I tried to break a piece. I also lit it on fire, but it turned purple. Odd...Very odd. Perhaps it has been imbued with magic, or simply created under different conditions. I'll keep a piece for myself, but the smithy can have the rest.