Powder flasks made of copper, brass or zinc are the successors of powder horns. They became cheap and affordable, when factories in Sheffield/England started to produce metal hardware during the industrial revolution in the 1820ies. Soon these powder flasks became very popular and uncountable factories and craftsmen produced powder flasks with various decorations (see also:
https://www.collectorsweekly.com/articles/the-metal-flask-successor-to-the-powder-horn/)
Here I´d like to show you six french prowder flasks from my small collection
1) Riling #881, Marquiset #238 (Sujet: Composé)
2) French powder flask (zinc body) shows a fox in a trap (Riling #1031)
3) Riling #586 (dead game)
4) Unknown (dead game, wild hog) I am not sure, that this powder flask is french, but it is no english design! Probably continental Europe. (later added: here (
https://www.ebay.de/itm/265156962195) you can see a similar flask, made by J.N.N. A PARIS)
5) French powder flask, sujet composé, not schown in "The powder flask book" nor in the Marquiset "poires á poudre"
6) French type Montgolfiere, like Riling #253 fluted