Dear all, with the precious help from Jeff and all the others who have contributed a final and authoritative word has put to rest the issue on the colour of chrono hands on Lemania 5100 Heuers. However here's already another one...

While reading the data of the 5100 Carreras of mid-Eighties (510.511 and 510.523) on the magnificent OtD scan copies of the period's catalogues, I found out to my bewilderment that one of them states "mineral glass, waterproof to 100 m" while yr 1985 one states "plexy glass, waterproof to 30 m".
Now, all these Carreras I've had the occasion to see in person don plexy glasses but I can't help wondering: are there any "super Carreras" with mineral glass around?
I would be more than surprised, but since the source is such an important one...
I am not sure if the issue has been already debated, so...any cues anyone?
Thanks in advance.
Fabrizio