I think it is possibly a Continental pocket flask as opposed to a Colonial one (because of the carving to flatten around the "teeter points" around the pontil, which I read was something to be found on British flasks). It is daisy within diamond over flutes in design. I have seen this flask in amethyst but never in this shade of green. 2 things: the camera isn't very good and doesn't capture the color quite, which is deep forest with a hint of teal. The photos were also taken at night, and the flask is reflecting surrounding shapes and colors.
Any help would be very appreciated!