Robert, I've been lead to belive that Rolex never 'actually made' any pocket watches or any parts for them. Cortebert actually supplied the pocket watch ebauches for Rolex to finish.
Always willing to learn though if I've been given a bum steer!
John
Posts: 1282 | Location: Northern England, United Kingdom | Registered: January 07, 2006
The key to this may be "assembled" so I'll take shot at it.
If I remember correctly there was a form of cooperative venture between Rolex and Gruen at one point or more in their histories. So, perhaps since Bob placed this in with the "American" section the answer for when a genuine Rolex is not a Rolex could be when they were Rolex made Gruens intended for the US market.
Lindell
Posts: 10553 | Location: Northeastern Ohio in the USA | Registered: November 19, 2002
ANSWER When the movement is marked Jules Jurgensen. Below is a picture of the movement. It is a 17j very thin unadjusted movement--probably made in the 1930s.
To be anti magnetic a Pallidium hairspring was used.The hour hand is driven off the winding barrel.
The watch is probably labelled unadjusted to lower the import duty.
Note the unusual layout and the 3 stars *** under the regulator arm. The 3 stars was used by Rolex to indicate their highest grade.
Posts: 621 | Location: Vallejo, California U.S.A. | Registered: July 10, 2004
Far too often names like Jules Jurgenson are not fully appreciated by collectors, this is another instance where digging a bit deeper can be very worthwhile. Thanks Bob, you really have a treasure there.
Lindell
Posts: 10553 | Location: Northeastern Ohio in the USA | Registered: November 19, 2002
Rolex Prince Imperial (observatory) movement in a Stainless Steel Case--17j 8 adj chronometer rated. Notice that the plates are the same as the Jules Jurgensen mvt.
Posts: 621 | Location: Vallejo, California U.S.A. | Registered: July 10, 2004
I am surprised that no one has commented that a 17 jewel dress watch can receive a chronometer rating and probably is as accurate as the best RR watches
Bob
Posts: 621 | Location: Vallejo, California U.S.A. | Registered: July 10, 2004
Thanks Bob, you really have a treasure there. 
