I'm lucky enough to have a couple of friends at a glass blowing studio. We're dorking around with making the Memory and Felix Felicis vials from Half-blood Prince.
The process is fairly simple: We sit down and discuss the reference photos and the guys go into the hot shop (where the glass blowing is done) and work up prototypes. We then sit down again and the prototypes are marked up with Sharpie and the process begins all over again. When they are done they'll be able to reproduce them fairly accurately (of course each one is hand-blown, so each one will be unique). The guys were pretty sure the pieces in the movie were hand-blown.
These are the first prototypes. For size reference, the large felix vial could hold almost a shot glass:
The process is fairly simple: We sit down and discuss the reference photos and the guys go into the hot shop (where the glass blowing is done) and work up prototypes. We then sit down again and the prototypes are marked up with Sharpie and the process begins all over again. When they are done they'll be able to reproduce them fairly accurately (of course each one is hand-blown, so each one will be unique). The guys were pretty sure the pieces in the movie were hand-blown.
These are the first prototypes. For size reference, the large felix vial could hold almost a shot glass: