my mate had this problem with his miroku. talking to the lads one night in pub this lad said we can sort it. I work in a jewellers s shop and we can clean it up. we clean gold,silver,titanium,diamonds etc that's easy.took the photos of gun damage to the shop and they can do it. the jeweller did it to a treat brilliant job. he said a lot of metal polishers contain bleach but don't tell you put some on a piece of stainless steel and watch it stain it.From the photos around that pin as you describe it it is black,look to your right and that engraving that looks like a Spanish fan follow the circle round and you can see black build up on engraving. the jeweller said shotgun engraving these days is very good and sometimes in deep engraving you get a build up of grime and muck if not cleaned properly. You do not have to pay over the odds to have a shotgun metal work cleaned. Sorted my mates gun out brilliant. Do not walk into a jewellers shop with a shotgun in a slip, doors will lock. staff will leg it,shutters will come down, and you will be surrounded by armed response police. And will need a new change of underpants. no expert myself in shooting but can hold my own. don't like to see fellow shooters ripped off by rfd when there is alternatives. Cost him 40 quid but he said he would get that back by a trade in or private sale looks great. I MAY get people not agreeing with me on this issue but it worked for my mate. There isn't only a gunsmith that can clean a gun.
