Dirtykneesrus, since your question indicates you don't know much at all about civil war relics, I'll add some info to what Steve in PA said about your button. By the way, I'm not putting you down - I myself had to ask "What is this?" the first time I dug the kind of button you dug.
In military lingo, a "general-service" button means the type issued on the uniform of an Enlisted Men (a non-officer, such as a private, corporal, or sargeant). Therefore, yankee "general service" buttons are the very most common military button of the civil war era. US Army regulations specified that general-service buttons were NOT to be gilded (gold-plated buttons were intended to be reserved for officers only). Relic-diggers and collectors almost always call this particular model of button simply an "eagle button." In dug but NICE condition - like yours is - one usually sells for around $4 to $5 at Virginia civil war relic shows.
A similar-looking button for lower-ranking officers (lieutenants and captains) contained a letter in the center of the shield (and were usually gold-plated). The leters are:
A = Artillery
C = Cavalry (specifically, Light Cavalry)
D = Dragoons (specifically, Heavy Cavalry)
I = Infantry
R = Riflemen
V = Voltiguers (rocketeers)
Regards,
TheCannonballGuy (PCGeorge)
