Your picture would be rated as poor at best... no offense... but you are gonna have to do alittle better than that before any information could be derived... at least I speak for myself anyway.
Close up... "macro mode". several please and the entire item pics would be nice as well.
Here is the rest of what I believe is a watch fob. medal is about 2 cm long and both sides are the same. Appears to be a hotair balloon. View attachment 1892652
18th century depiction of a balloon, I'd say it was French, so look for a French mark, might be a one of piece. Are those screws on the face of the plate.
I would look for a story of balloonist ending his days in the sea, or one shipwrecked taking his balloon to be first to attempt a crossing by balloon. Nice find and like all find you know have something to research and learn from. Any famous balloonist noted in history where you Live?