Jaeger-LeCoultre

…and finally decided to look for my fellow experts’ opinion. In general terms, the more jewels a movement has the more complicated it should be. The RDM is a 41 jewels movement. The Master Calendar is also a 41 jewels movement but with a full calendar, mo... 

…all the three models movements I’ve referred to have more parts than the RDM’s, but the jewels number question stays open Marcelo

The number of jewels and the level of complication, Marcelo. A GP WW TC has a Date, a Chrono, and a WT function. Its movement is more than 60 jewels. (!!! ) The U.N Sonata is a big date, Alarm, Alarm Countdown, and Dual Time zone Complication watch. Its m... 

My answer would be the more moving parts; the more jewels. I understand that Rolex tries to reduce parts, so less moving parts, hence less friction and no need for loads of jewels. Somewhere I read that the Valjoux 7750 uses nylon parts in the movement wh...