Watch SafeHorology glossaryDefined term / t-swiss-t
T Swiss T
A dial marking at six o'clock indicating tritium lume, one of several small Swiss dial texts whose wording encodes which luminous material the dial originally carried.
Authentication note
Why this detail matters.
The dial text must agree with the lume: T markings belong with tritium-era production, while later Swiss or Swiss Made wording accompanies newer materials. A dial whose marking contradicts its glowing modern lume has been relumed or replaced. These few millimeters of text are among the highest-value details in vintage dial assessment.