I think your crystal was fit very snug with very little crystal seal.
Is it possible you had a minute crack to start with and when the watch was subjected to lower temperature
there was just enough movement to let this crack continue?
Just trying to find an explanation or you have ghosts in your house... ;)
I would like to know where I can find this black crown for my Porsche Design watch with the same movement.

: Last night I found one of my watches not looking how I left it. The
: mineral glass had shattered. It was fine a week ago!
: It's been sitting in a padded drawer where it couldn't have been
: knocked or damaged.

: I know the glass isn't factory, as it is (was) domed, I can only
: presume it was a tad too big & popped.

: Does anyone know the correct size glass for a 510.501 Lemania
: 5100.. here are the before & after pics...

: Before...
:
:

: After...
:
:

: Stewart