No,, it would not be a powder flask !! If it came from a dealer no telling what its origin was !! Many are still getting items from the middle east and other places !! Many are still buying from the UK !! May have gone through several hands before your dealer got it !! The two possibilities I thought of especially since it had the spoon was either snuff which was quite popular with both men and women from colonial times !! A small pinch was either sniffed or placed between the lower lip and gums !! But this container is not typical for being made in the U.S. !! One thing I noticed were the two loops on either side !! Perhaps to attach to a chatelaine which was worn around the waist along with other things a lady might need !! What went on a chatelaine was a very individual thing depending on the lady !! This just looks a bit large for that but,,,you never know !!
The other possibility if its from the middle east is possibly for cocaine !! It has been quite common over the years in many places !! Haven`t checked but it may still be used in some countries !!
If its OK with you,, I will cross post this to another forum for more ideas !! We have some excellent researchers there !! I will post a link for you to follow !! Just let me know !!