MIKE STOP! PLEASE!
If that is some kind of residue, it can easily be removed with some plain old Carbuerator Cleaner from the Auto Zone! The Spray type for .99 a can. Keep it away from the Grip! Best stuff there is and leaves NO RESIDUE! Just spray it on and wipe it down with a soft Cloth. I use that when refinishing scabbards or doing any kind of metal fitting cleanup! You will, of course not remove any scratches or pits because there is NO abrasive in it. But it will be CLEAN! Also fine to use on crossguards or any other metal, but take the dagger apart before using it on Crossguards because you don't want to get it on the wood! Also, DON'T use it on anything Painted, like the scabbard shell, as it removes EVERYTHING.
3-Finger Louie
