: This is extremely intriguing!
: I don’t think I’ve ever seen such a Heuer model - in
: catalogues, picture or any sales platforms.
: I also am firmly convinced that Heuer did not start using Lemania
: movements until they were bought by them. I am baffled by the
: various places your watch is signed: the shield on the dial is
: very well made, but the one on the caseback inside not so much -
: though they sometimes are also on watches that are known to be
: certainly genuine.
: Furthermore most brands that did use the 1341 did not engrave the
: oscillating mass as far as I can remember. And the use of this
: movement- which was costlier than its successor 5100 - pre-dates
: the “parts bin” days considerably.
: All things considered, I am torn between non genuine or something
: of a prototype that never made it to a production run. Either
: way, your watch is very nice, and the movement is a high-quality
: one. So aside the very natural curiosity I’d suggest enjoying
: it as is, regardless of whether you’ll be able to ascertain
: its veracity for sure.
: Cheers,
: Fabrizio

For what it's worth, Fabrizio, I have been doing some thinking on it, though I am sure I will put right soon enough :-)

this watch has really piqued my interest as two experienced Swiss trained watchmakers (though both Rolex trained) who have had it in their hands can't find anything to suggest the dial is fake and if it is fake it's one of the best they have seen. The case, movement is all correct for the 9801 and the Cal.1341 fits for a watch c.1970-75 I guess. So the case and movement can be accounted for. It's just that dial. A Heuer experienced watchmaker suggests it could have be a one off special order. Just a guess of course. In regards the lume: There is a small amount of phosphorous to keep the tritium weakly charged for about 10-15 secs, if that.

One interesting set of facts I came across recently (though I know you and other experts are clearly aware of this), suggests that the success of the 1960s Chronograph was seen as a boon to the Swiss watch industry in the 1960s, with 50,000 + units sold in 1964 to more than 170,000 in 1969. However, it appears, that this was not enough for the 70s and a "new boost was needed. An automatic chronograph was the solution." It was the Central Minutes Chronograph that was ostensibly going to be that boost. It appears there was a move by many watch brands to get these produced and onto the market including Lemania, Bucherer, Tissot, Dugena, Darwil, Mate, Nivada, et al. but using the cal.1340 (and possibly 1341?). Now, purely supposition here of course, but is it possible that Heuer, not to miss out, created a one off dial to investigate the use of a central minutes chronograph but events overtook them as the "Quartz invasion" became unrelenting. Could this account for the early 70s C Case and the Cal. 1341? I can see it put together as a one-off but not into production. However, I can't see Heuer wanting to use a Lemania when the Valjoux was their goto movement and having to go into R & D to develop their own would have been difficult in terms of funding at that time. Just guessing of course.

I believe that In the mid 70s Heuer produced the Chronosplit and maybe they backed that over the Minutes Chrono in those years? I know they followed up in 1977 with the auto chronos Kentucky and Pasadena models using the Valjoux 7750, but these were three-register chronos.

I believe that Tag-Heuer, In the mid-1980s, began using the less expensive Lemania 5100 movement when their was the Heuer/Lemania unison which did have the minute hand for the chronograph on the centre pinion - so maybe they just couldn't contractually meet with Lemania until that union and by hen it was too late.

I know that this all sounds like a long bow drawn, and of course pure speculation, but as of now I can't prove the dial a fake and if it's not then there must be some rational explanation. This seems as reasonable as any another. Problem is, Ockam's razor is always lurking in the background of my thinking. Speaking of Ocham's Razor, why fake a Heuer dial and Case back when there would be no financial advantage that I can see in doing so? I know that the unfurbished version of this watch was sold in 1987 and then on sold to a watchmaker in 2017 who refurbished it and then held it until I got it this year.

Either way, Curiosity has got the better of me, but I am thankful I bought it because I love that case & dial and the movement isn't too bad either. :-).