Serial Number Range: 16xxxxx-29xxxxx
General Notes: The Mark 1 or “Long E” dial was the erstwhile earliest matte dial variation before the Mark 0 was recognized. The nickname for this dial comes from the middle bar of the E in Rolex, which is much longer than on other variations and is unique to this dial.
Distinguishing Characteristics: The Mark 1 dial is very easy to pick out amongst matte dial 1675s. Look first at the coronet and then look at the E in Rolex. If the coronet is string-like and the E has a long middle bar, it is a Mark 1.
Subtypes: There are a number of changes that occur within the Mark 1. All ranges listed below are estimates and not definitive cutoffs. You can see watches with the ‘wrong’ characteristics just to either side of the SN transition points listed below.
- Hand Size and Shape:
- SN 1.6-1.8m — both the flat and curved hour/minute hands and the small and large 24-hour hand can be seen. With a small 24-hour hand, these are referred to as Mark 0.5 dials. There is no hard rule about which serials have which hand size or shape. Proportionately, more watches in the earlier part of the range (i.e., nearer 1.6m) have the gilt-era characteristics of flat hands and small 24-hour hand.
- SN 1.9-2.9m — curved hour hands and large 24-hour hands are seen.
- Lume:
- SN 1.6-1.8m — Zinc sulfide dials were still used (a carry over from the gilt era). These appear more puffy and maintains phosphorescence when exposed to UV light.
- SN 1.9-2.9m — The lume has a waffle like texture, is more flat, and the reaction to UV light is minimal or is segregated to small crystals within the lume. The hands maintain UV consistency with the dials in both cases
- Case:
- SN 1.6-1.8m — ‘thin’ cases, which were 12.7 mm thick.
- SN 1.8-2.9m — standard case, which were 13.0 mm thick.
Pictures
Pictures Credit: Michael Morgan, Lee Fowler, Rolstaff of TRF
Rolex GMT Master 1675 