According to Oldwatch.com, the first step involved in identifying old pocket watches is determining the type of watch, and then finding information from the movement. Generally, the three types of pocket watches are the hunting case pocket watch, the open face pocket watch and the sidewinder pocket watch.
A hunting case pocket watch has a closed cover over the face of the watch, while an open face pocket watch has no cover on the face of the watch, explains Oldwatch.com. A sidewinder pocket watch has no cover over the face of the watch and winds at the 3 o'clock position. It has an open face case and a hunting case pocket watch movement.
Pamela Wiggins explains on About.com that antique pocket watches were created differently. Some of the most valuable watches are railroad pocket watches that were made according to government-required exacting standards to ensure they maintained accurate time. Other important factors that add to a pocket watch’s value include the number of jewels and the number of adjustments that come with it, and its age. The adjustments refer to the calibrations a pocket watch has to keep it running accurately depending on the position in which it is held.