Ignis will help with smelting the metal, but the heat from the forge will cook you in yer boots!
Our ancestors, the dwarves who forged Aegrim's armor, could sustain their stoneform for far longer than we can today. That's how they could forge the bulwark in the first place.
Luckily, my friend Bouldercrag can help us with that. He'll need some materials for the ritual.