Serial Number Range: 5032xx – 505xxx, 680xxx*
General Notes: The first dials of the 1675 retain the “Officially Certified / Chronometer” (OCC) text of the 6542 dial. This difference stems from the transitional nature of these early examples. The OCC texts signifies that the movement underneath is not the 1565 calibre seen on all later 1675 models but houses the earlier 1535 (itself somewhat of a transition from the 10xx to 15xx calibre movements) without the microstella adjustment. As this is a transitional period, OCC dials have been seen with the newer 1565 movements (marked 1560, which is the base calibre). After these dials, all subsequent 1675 iterations are printed with Rolex’s then new “Superlative Chronometer / Officially Certified” moniker.
OCC dials are consistently seen with case backs stamped “II.59” or “I.60” – most are the I.60 stamp. I would be suspicious of any other case backs. III.59 or IV.59, which would logically come between the two known date stamps, were probably not made because of batch production.
Much of the knowledge about this interesting dial and transitional period is due to the work of Stefano Mazzariol, who deserves our thanks.
Pictures
Picture Credit: Rolstaff of VRF
*Eric Ku has shown us two OCC dialed examples (1,2) with underlines – one with serial 680xxx, the other is unknown to me. These dials seem to have the same characteristics as the non-underline versions. I would only trust someone like him to verify a piece like this if you come across one.
Rolex GMT Master 1675 