Nice digs, Giant. WTG on a nice knife and love the button. Have you dated it at all? The Latin translates, "I look back and now depart." Very cool relic!
HH
Cannonball man looked it up in what I guess is a button book and he said that it's a livery button made from 1823-1830s, it could have been from a butler, carriage driver or any uniform that has to do with livery. It was probably an immigrant from England that was wearing the coat way back when and lost it. I can only imagine