Bill_S wrote:
> Any suggestions on how to clean it up better? I will try to clean it up and get some better pics.
I've been thinking that the markings on the blades and clamshells are going to be the key remaining clues for identifying the pin, so I've been intending to suggest that cleaning would show the markings on the blades and clamshells better ...but I was waiting for you to reappear in this discussion.
I'd recommend submerging the pin in straight household ammonia for 90 seconds, then quickly remove the pin, and gently brush the marked areas with the tip of a toothbrush which has been dipped in the ammonia. Such a short time (90 seconds) isn't long enough for the ammonia to harm the relic. If you prefer, you can use a 50/50 solution of ammonia and water. Just be sure (after you've done the gentle toothbrushing) to rinse the relic thoroughly under running water, to remove all the ammonia.
If 90 seconds turns out not to be enough, you can repeat the ammonia-soaking. But because the dirt-crust on your pin looks thin, I think 90 seconds (followed immediately by toothbrushing) will be enough.
I should mention here that some relics are too corroded to use ammonia on without harming them. But your pins appears to have very little corrosion. If you're worried, use 50/50 ammonia & water.