Always good when there is a positive outcome. You would think it would happen more often in this age of Googling info, but every so often we get someone coming to this forum to tell us of a shell they found.
I recall two successful instances, and there were many more where the "projectile" was just a metallic spheroid. One woman in Maryland had what we informed her was a 12pdr sideloader. She decided she wanted to keep it, but we got her to somebody who could take it to get inerted for her and returned safely. Another guy found a Read bolt in his late father-in-law’s closet, and we set him straight as to what it was and helped him get a fair price for it too. Hopefully, more people will find us here when they have these types of finds and let us help them.