[@LadyRunic] What's the point of having iron if it's not harmful?  I mean, it's good for working with, but honestly, fey have other metals that are far easier to obtain and just as good, if not better.  The benefit of iron is that it is lethal.  I was under the impression that some fey could handle iron, like the...was it goblins?  Also, both Nyx and Sini's mother had blades with flecks of iron, though I think Duska gave hers to the captain that followed her.  I actually didn't catch the bit about the captain of the guard, or I would have gone with it already for Sini.

To be harmful, the iron must come into contact with the fey or the magic, right?  Toxic, but minor injuries will heal eventually, just not as fast, and they get far worse far faster than other injuries, and do more damage.  But this means having iron on the blade of a weapon is like coating it in poison.  As long as you don't touch it directly, you're okay.  Makes maintaining said blade interesting, because it's a contact poison as opposed to needing to reach the bloodstream to have any effect, but I imagine it can be done.  Gloves, caution...maybe serious work is handed over to iron-resistant smiths.