The changeling blessed with it can use his supernatural skill with metallurgy to alter metal objects, improving them, even if improving them would normally be impossible. The player spends one Glamour and makes an extended roll of Dexterity + Crafts, with each roll representing half an hour of tinkering, polishing and hammering. If the changeling manages to gather four successes, he can alter a tool so that it gives a +1 equipment bonus. The item has to mostly be made of metal. The magic wears off after a day. No object this way can be improved more than three times. If the changeling tries to alter an object a fourth time, he destroys the tool, and it can never be used again.
To maintain effectiveness as a weapon against the True Fae, handforged iron cannot be subject to the heat of the forge. This means if the weapon breaks or must be re-forged, the best that can be done is to remake it into two or more smaller weapons. Wizened of the Smith kith have discovered a partial way around this requirement, albeit at great cost. By spending a dot of Willpower, a Smith can apply just enough heat to forge the pieces of a hand-forged iron blade back together. This same expenditure allows the Smith to begin the process of hand-forging with an ingot of cast or wrought iron; anyone else must start with meteoric iron. This ability is considered part of the kith’s blessing.