MikeTheWatchGuy Messages: 319 Registered: May 2013 Location: North Carolina
Gruen Guildsman
They may have co-existed, but I think the 826 came later. It doesn't show up in the catalogs until the 1930's where the 825 and 827 were both in the 1926 catalog, the 827 in the 1929 Guild book. Unfortunately it's a 10-year gap until the 1939 catalog.
While digging, I found an email (2009 no less) from someone wanting information on their watch with an 827 case that housed and 826 movement. I am unable to find the picture that went with it however so it could be one of the ones we have.
There have been a ton of 826 based watches on ebay, one as recently as last October in a ladies pendant watch. I can't make out the case. And Holben had a sterling silver one with an 826 but nothing but sterling stamped in the back. However, he also had a 3-piece case ladies watch with an 827 in it. I found a ladies fixed lug with an 827 case, but don't know the movement.
So, cursory look at ebay past, 826's are not all that rare and they appear in ladies and mens watches. 827's are rare.