Here are some better pics. Thanks Cru for the info. I haven't cleaned it yet but does look like some silver gilt left on it. I thought it looked like a ships wheel also Old Dude...hoping it was military! Thanks again for the input and hope everyone has a great day.
Like Cru said, late 18th - very early 19th century decorative civilian button. I would go back to that spot - there may be some more coins, buttons or other relics from the same period.