Oh boy… just soldered some posts on a silver earrings - after I
polished the piece noticed firescale (AHHHH) any quick fixes for
this to cover it up???
Go back to tripoli or white diamond compound, and buff a bit more
deeply. A bristle brush may work well. buff through the fire scale.
If it’s not too severe, this shouldn’t be too hard to do.
If that won’t work, silver plate it. You need a rectifier or
appropriate batteries, and silver plating solution, of which the most
effective are cyanide based, so if you’re not familier with this, you
might want to find someone who can do it for you.