The industrial production of metal powder flasks started around 1820. Before this time some metal powder flasks have been made by craftsmen. Silver- and coppersmiths were able to make the bodies of powder flasks all the time before the mass production started.
In the book of Marquiset, POIRES A POUDRE there are some pictures of round metal powder flasks from the end of the XVIII century.
Until around 1800 most of the powder flasks have been made using horn.
But is is not easy to fix an exact date, when a flask was made because most of the flasks or horns have no markings of the maker.
This might have bern made for a flintlock gun, because there is a needle (for cleaning the touchhole???) on the wooden stopper
Very simple flat horn. I got no idea, when it was made.
This flask has a body made of copper and a head made of horn. Early flask? Or made in the end of the XIX century?