Blancpain

hs111
16540

• Show profile
• Show other posts

What I forgot.. Just one more little Q be allowed, pls..

On your nifty picture with the nice eclipse,
- one thing popped oup in my mind, when looking
more in detail on the inscription of the caseback:

- These inscriptions and signs have always fascinated me, and were an add'l educational kick & riddle about the TR's of yours..

I realized, there is even an pretty exact number ( 2 milli-Curie) for the
beta-emitting element / isotope Pm 147 .
- I guess, that is Promethium 147, with a half-time of 2,62.Years;
- given the production or manufacturing inscription (?) of II / 64 , that leaves us after 50 yrs
and 19.1 half-lives with a negligible residual radioactivity, which indeed is very low,
(and would also not penetrate the caseback). Interestingly, when mixed with Phosphor ( P) , it was used to illuminate Apollo Lunar Module
electrical switch tips and painted on control panels of the Lunar Roving Vehicle
( ref Apollo Experience Report- Protection against Radiation. NASA, retrieved Dec 2011).

My little question is twofold:
a) have all TR's the same type of caseback inscriptions ?
b) what about the military FF's ? ( like Milspec etc, where probably (?) Tritium
( or Radium (?) then replaced by Tritium ??) was used

Hope I don't bother you with those dwellings,
- just another 2-cent riddle..

Best, hs

Site Info.