You may be right that it's not RR related and in fact 'just' a lead seal of sorts. Found on old RR track. I'll green check on lead seal. It would make sense that RR seals were marked.
If I follow the trail too much further I won't be able to continue detecting without further obtained permission as it would be right in middle site of the battle of Guilford Courthouse
I do agree that former RR tracks can produce high number of targets with good stuff included
Hey, I've detected near there IS. Keep looking around there. Gain your permission to detect and do some research. Good history around there my friend. Yes, Dale. I find most of my stuff (near) RR tracks. Those RR tracks were used by all walks of life through the years and If you find the right field that buts up to them, you could have a field day. Literally! You know that though.