Ironbark

Ironbark is a unique substance that is stronger and lighter than steel, making it a good material for weapons though it is used for making other things as well. The Dalish Elves appears to be the only ones that can mold the ironbark as they do. As only the Dalish can make it, it is seldom seen in the hands of humans, though one can assume that it may be one of the primarily items the Dalish trade with humans for other things they may need. As it is, a weapon or suchlike of ironbark is unusal enough to make a good weapon or fetch a good price from anyone.

Trivia
In Dragon Age: The Stolen Throne, Loghain remembers an elf named Potter from his camp who once got a ironbark blade from some Dalish Elves (or so he claimed) that he later pawned for a good price. Likewise, Loghain also notes that a young Dalish elf has an ironbark amulet which the elf in question claims was a gift from the clan's Keeper.