I have never seen a grave marker like that, but I don't doubt it, From 76 - 90 I've enjoyed metal detecting & specializing in farm fields where old homesteads used to be, (always asked permission) Found many civil war buttions & etc. Sometimes found rare things which I thought & did donate them to the meseum they squireled them away & I never saw them again. Oh well such as life, also found rings, if identifable, I returned, Sometimes we find things which we hold for reserch. I belong to the Sons of union vetrans of the civil war, we hold a lot of civil war cermonies at cemeteries & never saw or looked for a marker like that, but will from now on. the SUVCW has a lot of imf. on thinge like that. Should call ( The National Sons of the SUVCW not the local. Jmsuvcw@aol.com Have a musket, " ball"! Ken.