Can anyone please help me identify if my vintage '77 Omega Seamaster would have a Tritium dial?

[nickelus]

Hi all,

I have a vintage Omega Seamaster which I'm told is from 1977 and has the original dial, yet there are no 't's on the dial, indicating the presence of Tritium.

As far as I understand, all watches after the 60s used Tritium, and they had to be marked with a 't' to indicate this. To add to the confusion, if I hold the watch in direct sunlight for a few minutes, when I go into a pitch-black room, the markers still glow. However, if this was tritium, considering the half-life I wouldn't expect it to glow at all.

I'm fairly new to the watch-game, so I was hoping one of you might be able to shed some light and help answer my query.

Many thanks!

 

[asrnj77]

The dial looks like others I’ve seen from that era. You should search 166.0215 and look at others to compare. I have some tritium watches where the lume still glows briefly. It’s the paint they used that’s glowing, not the tritium. If it lasts less than a minute or two, I think it’s probably original.

 

[Foo2rama]

I see tritium dots at the end of the hour markers. Looks like some in the hands as well. It’s way past it’s useful date. Back in the day tritium would glow from the radioactive decay. But tritium has a short 1/2 life so it’s no longer strong enough to glow on its own.

they should stay lit for a very brief amount of time if exposed to bright light from a flashlight and then turn off the lights.

think seconds. If it stays decently lit for over a minute it’s luminova but I doubt it here.


Also it could only have tritium. Radium was gone by the early 60’s and luminova started around the early 80’s and was totally phased out in 1999

Edited: Oct 2, 2021

 

[ckhaing]

this 70's seamaster also has lume dots but no T marking

Edited: Oct 3, 2021

 

[padders]

On Omegas at least, virtually everything* between 1963 and 1998 used tritium. Then SuperLuminova came in. SL is just a trade name for doped Strontium Aluminate, the same thing (or similar) is branded differently by different by manufacturers. The T marks are not always present even when tritium was used. My take on it is that once the amount of radioactive emissions fell below a certain level, there was no longer a legal requirement to report it on the dial so they didn’t in some cases. The early Bond SMP and plenty of other Omegas from the 70s onwards definitely used tritium yet there are no T marks seen.

The OP watch could of course have been relumed at some point with or had a later replacement dial, the colour looks awfully white for decayed tritium but it’s more likely it’s just original tritium. The Zinc sulphide in tritium lume will glow briefly when excited by light or uv but won’t persist since the beta radiation from the tritium component is negligible after ~4 half lives.

*there were a few military Omegas that continued to use Radium later into the 60s it seems. Some of the Seamaster marked Railmasters seem to use Radium for instance. There are extracts that mention radium lume in the text for watches delivered to PAF into the 70s, though that could be a mistake.

Edited: Oct 4, 2021

 

[ConElPueblo]

padders

On Omegas at least, virtually everything* between 1963 and 1998 used tritium. Then SuperLuminova came in. SL is just a trade name for doped Strontium Aluminate, the same thing (or similar) is branded differently by different by manufacturers. The T marks are not always present even when tritium was used. My take on it is that once the amount of radioactive emissions fell below a certain level, there was no longer a legal requirement to report it on the dial so they didn’t in some cases. The early Bond SMP and plenty of other Omegas from the 70s onwards definitely used tritium yet there are no T marks seen.

This is my take as well. I would speculate that the formula was changed at some point in the seventies as I have experienced that it ages and deterioates differently from earlier tritium dials.