All about Gruen

[Fred]

https://www.ebay.com/itm/195784194121

Looks like a stamped 107 caliber; 56A—a model number?

Anyway, not sure where to post, but I’d love to hear your thoughts.

[Dietrich]

Yes, agree, looks like a Gübelin stamped cal. 107. Looks like there is even a small GR visible at the lower left of the Gübelin, 17Jewels... stamped bridge.
The "A" right of the 56 might not belong to the 56 as it is a differnt larger font andthe depth of the marking is differing a lot. Therefore I would see this oe separately and would see it as a hint towards Alpina which might close the circle. A Gruen Alpina model from their collaborative time supplied to Gübelin?

[Fred]

This Alpina lens is a good one. The watch struck me as being marked wholly consistent with one for US import. I’ve not looked for or captured many Alpina images. Is this movement marking (adjs etc) what you’ve seen there usually?

The 56A if viewed together reminds me of the highest-end model numbers from the old Worthy Company pubs, what I’ve called the Platinum line, since many were cased in it. There, it was reversed, like this A103 :

[Mr. Bieser]

Interesting watch in link, thanks for sharing. I've noticed in "platinum line" several letters used to the left of the calibre number, A, E, O, etc.

Hope you don't mind me piggybacking an interesting link. An Alpina Gruen with a gold case from Ohio with the German Crown, don't see many of those!
https://www.ebay.com/itm/134582714578

[Fred]

Whoa, that is a first! At least for me. So many questions which I cannot even yet formulate. Thanks very much for sharing, Mr. Bieser.