Ah, the hey-day of the "jewel wars"!
So bad were they that some companies took to gluing non-functional jewels (synthetic rubies, mostly) to useless places (like on the rotor) just to hike up the jewel count :)
You should open it up just to see!
When I was growing up, there was an older than God Swiss Watchmaker at the end of our block. . . he looked just like you would expect a Swiss Watchmaker would look like, fringe of white hair, apple cheeks, and a little smile, but somehow he missed the lederhosen. He said that there were really only 19 bearing points on a standard watch that really needed a jewel. Everything else would be superfluous. If you added complications, then you might need a few more. . . but never as many as you might think.