“No, no, no - I'm not all of the sudden saying that the ring is mine. I normally don't do this, but your information about the Dark Irons was very useful. I'll improve your ring for you, better than whomever made this simple little thing could have ever done. Probably some gnome...
If you bring me a bar of silver, a moss agate, and thirty silver coins for my trouble, I'll add a silver and agate lattice to the ring that will strengthen the magic inside of it. Interested?”
