Military button help

[pistol-pete]

Dug this button a couple days ago, and am not familiar with these. It's high dome and measures .770 inches, which is a different size than any I have in a box of stuff. Can any of you tell me exactly what it could be? Age, garment etc. Thanks

 

[relic lover]

Indian wars era I think

sent from my computer by frantically poking at the keyboard with a single finger

 

[geologyjohn]

Its a Federal (Union) "General Service" coat button from the Civil War. Nice to dig one in that condition. Good find!