“T Swiss Made T” Doesn’t Always Mean a Rolex Dial Has Tritium

Before about 1962, the luminous paint that Rolex (and the whole watch industry) used was based on highly radioactive radium. Since the late 1990’s, non-radioactive pigments based on strontium aluminate have been the standard, sold under many brand names like Super-LumiNova and Rolex’s Chromalight. But in between those years, the glowing paint used for watch dials and hands contained tritium, which is radioactive but with a much shorter half-life than radium. Tritium Rolex dials always have “T Swiss Made T”, “T Swiss T” or “Swiss-T<25” at the bottom. In some cases, though, a dial may have the T’s even though it doesn’t have tritium.

Since 1964, it has been Swiss law that any watch with tritium must be marked with a “T” on the dial. But there’s a common misconception that unlumed Rolex watches from the tritium era don’t have the T’s on the dial. In reality, Rolex seemed to print “T Swiss Made T” (or “T Swiss T” or “Swiss-T<25”) on every dial, with the lume application being the final step in the process. If a watch didn’t get lume, no problem–the “T” being on the dial didn’t hurt anything. Let’s quickly go over all the Rolex “T Swiss Made T” dials that don’t actually have tritium.

Unlumed Rolex Dials From 1962-1998 Usually Say “T Swiss Made T”

The majority of Rolex watches from the tritium era (roughly 1962-1998) do have lume. But some simply don’t, and they come with unpainted hands. In most cases they still say “T Swiss T” (with or without “Made”) at the bottom of the dial. Many of these unlumed dials are found in Japan, where tritium products faced prohibitive import restrictions for many years.

There’s another type of unlumed Rolex that was only made from about 1967-1973: models with black vitreous enamel accents. Where lume would normally be on the hands, there’s rich black enamel instead.

Usually on these models you’ll find black enamel accents on the hour markers as well. The highly collectible CERN Milgauss is the most well-known example of such a Rolex, and that says “T Swiss T” (no “Made”) at the bottom. But there are also some Datejusts and Oyster Perpetual Date models with black enamel instead of lume.

Rolex “T Swiss Made T” Dial With Super-Luminova = Tritinova

A “tritinova” Rolex dial is a dial that has modern Super-LumiNova lume despite having “T Swiss Made T” (or “T Swiss T” or “Swiss-T<25”) at the bottom. Usually these dials hail from the late 1990s, but there are examples of tritinova service dials that have appeared much later.

I personally had a new Air-King-Date dial swapped on at Rolex Service Center New York in 2011, and it has “T Swiss Made T” at the bottom despite having Super-LumiNova. This bolsters the notion that Rolex printed the T’s first and lumed the dials later. Rolex isn’t going to throw a bunch of dials in the trash just because they say “T” and they don’t have tritium–Rolex is notorious for using up their parts.

Lumed Hands But Unlumed Dial?

Unlumed Rolex dials almost always belong with unlumed hands, but there are exceptions, like wood dials. Those are unlumed, but (probably for the sake of contrast) Rolex decided to put lumed hands on them.

Because “T Swiss T” is at the bottom of the dial, Rolex could put tritium hands on there without breaking any laws. The “T’s” kept their options open.

So Rolex could put tritium-filled hands on Yacht-Masters with serti dials, for instance. Because sports models have so much more lume than non-sports models (largely thanks to their Mercedes hands) they say “Swiss-T<25” at the bottom, meaning it emits less than 25 millicuries of radiation. That actually means it emits more radiation than an unspecified Rolex T Swiss Made T dial, because an unspecified T has to emit less than 7.5 millicuries.

So Unlumed Vintage Rolex Dials Always Say T Swiss Made T?

We’ve established that unlumed vintage Rolex dials from the tritium era do in fact usually say “T Swiss Made T”, “T Swiss T”, or “Swiss-T<25”. But there are exceptions: some unlumed Jubilee dials and stone dials simply say “Swiss” or “Swiss Made.”

And naturally, aside from the aforementioned random leftover tritinova service dials, the “T’s” have been gone altogether since the late 1990’s when tritium went away. And if you’ve made it this far into my article about when Rolex put tiny T’s at the bottom of their dials, thank you for nerding out with me. Visit Grey Market regularly for more earth-shattering content like this.