That is a nice SC button indeed. I wish it could tell us its story of how it made it to Maine. It must have been an interesting journey. I once heard a story about a US belt plate being dug in Germany. It was believed that it was part a Civil War collection that was scattered into the rubble during WWII by an Allied bombing.
Great button and thanks for sharing it with T-Net!!
Civil war button alright. Just a guess but I'd say speculate some Maine volunteer got it as a souvinier, kids playing with it, lost it. remember, soldiers in every war pick up trophy's after a battle.