As mentioned, this research is for 3-register watches only.
Regardless of which of the three brands fit the following description (with exceptions noted in each brand section, below):
1. A running seconds at 9 o’clock, an hour register at 6 o’clock (12 hours), and a larger minute register at 3 o’clock
2. Black with white text and marks
3. Marks designating each hour (every 5 minutes) are non-luminous, relatively thick versus the opposing minute minutes, and extend to the outer edge of the dial. These marks extend as far toward the center of the dial as the other minute marks. When we see luminous marks they most often appear to be later additions to the dial.
4. Minute track of non-luminous marks that do not extend to the edge of the dial (as in above-mentioned hour marks)
5. Luminous hour numerals with exceptions of at 3, 6 and 9.
6. Numerals 2, 4 and 10 are cropped by the registers, with no luminous material extending into the registers. While there are pieces on which we see the ‘0’ in ’10’ not cropped, I do not believe this was the intended design. When we see non-cropped ‘0’s, there is no consistency in case number, and they often look flattened or simply proportionally smaller than the other hour numerals.
Again, here I am here referencing the “standard” dial, and not outlier dials, referenced below.
“FAB SUISSE” is on all dials at 6 o’clock, with the ‘SUI’ obscured by the thick 6 o’clock mark.
The Mathey-Tissot features two designs, both in white, for the brand and logo, as applicable, at 12 o’clock:
1. This design features a larger font for the ‘Mathey-Tissot’ name. The name aligns horizontally with the ’10’ and ‘2’ numerals. Vertically, the ‘M’ aligns with the left edge of the second ‘1’ in ’11’ on the dial, and the last “t” ends at approximately the right edge of the mark for 3 minutes on the minute track. There is no propeller/globe image on this dial.
2. The other design features smaller type for ‘Mathey-Tissot’, with an image of a propeller over a globe just below.
Running seconds register
Running seconds has marks at each second, with longer marks at each 5 second. There are numerals for 20, 40 and 60, with index marks that are slightly thicker than the other marks.
The ‘6’ is open by just a fraction. Seconds marks extend all the way to edge of the register.
12 hour register
There are two styles of 12-hour register:
a. The 12 hour register has marks for each 30 minutes including shortened marks at each hour, and numerals for each hour up to 12. Marks extend all the way to the edge of the register. This register has an open ‘6’ and ‘9’.
b. The second design has index marks on the half-hour, with only numerals on each hour (no marks). This register features a closed ‘6’ and ‘9’.
The larger minute register comes in two styles:
a. 15-minute register “design” and luminous marks at each 3rd mark (would be 3, 6, 9, 12, and 0/15 if running at 15 minutes). I mention this as “design” as there are a number of pieces we see that have the “15-minute register design”, but run at 30 minutes (there is some discussion about this online). I believe that given the relatively high number of pieces we see with 15-minute design but running at 30 minutes, that these are original to the watch (same holds for the other brands of Type XX discussed here). There are no numerals with this register design.
b. 30-minute register with numerals 10, 20 and 30. The marks at minutes 3, 6, and 9 are luminous, and are the longest. Marks at 5, 15, and 25 are next longest in length. All other marks at the same length, with the marks at 10, 20 and 30 differentiated by being slightly thicker than the others.
We also see one example of a Mathey-Tissot Type XX with a telemetre (Base 1000) track. Given there is just one (relumed and with yellow paint added to bezel triangle later), it is difficult to say that it was born with this configuration. This watch features the smaller typeface for branding, with propeller and dial, a 30-second subregister, no marks on the hour within the 12-hour register, and prominently cropped 2, 4, 8, and 10 due to the telemetre track presence.
In terms of what combinations we see of type/logo and registers, there are “no-globe” dials on pieces with a 15-minute or 30-minute register design.
“FAB SUISSE” is on all dials at 6 o’clock, with the ‘SUI’ obscured by the thick 6 o’clock mark in most all cases.
The Girard-Perregaux Type XX dial comes in two designs, most noticeably shown by the style of text used for the brand at 12 o’clock: either a combination of upper and lowercase, or all uppercase letters. Based on extremely limited serial number information, it appears that early productions were upper and lowercase, and the later were all uppercase.
Upper and lowercase Girard-Perregaux name
The Girard-Perregaux featuring lettering as ‘Girard-Perregaux’ will always have a minute register that has a 15-minute design, same as the Mathey-Tissot 15-minute design, with luminous marks at 0, 3, 6, 9 and 12.
All uppercase Girard-Perregaux name
The dials with branding shown as ‘GIRARD-PERREGAUX’ all have minute registers with 30-minute design. Again the design of the register is exactly as we see with Mathey-Tissot 30 minute registers, with luminous marks at 3, 6 and 9, and numerals shown for 10, 20 and 30.
Minute register design are noted above.
All dials have the same running seconds and 12-hour register design, which matches the second type of minute register design from Mathey-Tissot, above, with marks on the half-hour only, and numerals only for the hours.
There is one instance where we see the ‘SUISSE’ at 6 o’clock not obscured by the hour mark.
Unlike with Mathey-Tissot and Girard-Perregaux, ‘FAB SUISSE’ text does not appear on any dials.
Completely different very large Breguet logo
2970: Dial is different in nearly every respect in addition to the logo – the outer marks (numerals on the 5’s), hour numerals, registers, etc.
Alternative scale: Tachymeter
We also see two dials with tachymeter scales, below. While I can’t make any claims to their authenticity, whenever you see rare/uniques piece, it of course is an indicator to take a close look.
2993 (left, below): Sold at auction in 2018, this watch has clearly been serviced and at least polished. It is difficult to comment about the dial without seeing in person.
3012 (right, below): This features a tachymeter scale also, but the numerals as well as mark on the outer track are different than watch 2993, above. This watch also has a countdown bezel.