Another rare french button from my favorite military site: this button is one of Napoleons dragoons, formed when he was King of Italy and can be dated 1805-1812.
Folkert that is one keeper of a button.
I used to not be into buttons till I started finding some old ones that dated back to the late 1700' to 1800's. A couple of the buttons I have found are not very commone and I have yet to locate pictures of them.
Anyway this post is about your button.
That is an amazing find!