When it comes to steampunk and skeleton watches, you have several options. You know the person you are giving it to better than anyone else, so consider their personal style and don't just choose the first one you see.
Female models are thinner and more colorful. Small jewels are often integrated in or around the apparent mechanism to embellish the dial. But it is sometimes difficult to distinguish between the various influences of these watches ...
For the neophyte, a skeleton watch and a steampunk watch can look alike.
On the contrary.
Skeleton watches are, as their name suggests, essentially the skeleton of a watch dial. Most, if not all, of its internal parts are exposed to the eye and stylized to be fashionable. They can have a very minimalist or industrial look, depending on the watch.
Steampunk watches often have part of their inner mechanism exposed, but they usually have larger gears and sprockets, and are often decorated with metal to give them more luster. They are also often copper or bronze in color, which gives them an older look.
Again, both pieces are on display. Skeletons are usually a little more raw and naked, for lack of a better term. If in doubt, just tell the person that their watch is superb.