Almost died when I saw this button today!! Been detecting this farm for 2 years now. the house was built in 1789 i have found many buttons there but this will be my favorite button that i will ever find but u never know i could find another.
They don't come out like that very often.. I'm definitely giving you a banner vote and I think others should too. These things are kinda like Gold coins, everyone found should make banner.
Check out this link for identifying George Washington Inaugural buttons. Your button may not be a GW button, but it is VERY rare and worth as much as any GW button. Five or less known to exist, based on the rating given for that button!
I'm not a GWI button expert, but I found a different GWI button on eBay that sold for almost $700. That button was in rough condition and was rated R-6. So I would say that you have a button worth at least a grand and probably much higher than that! Congratulations!