Not sure when that existed. but really exotic jewelry custom cases were made there for p.w. and w.w. Probably 1916-20+. An example here sold cheaply because of only a couple cheap bidders including myself. I never expected to see one of these on ebay. It is a standard adjusted Verithin not a small size pendant watch, but a real pocket watch. Movement is original 461k which is before 1918. Case is likely unique. Platinum and good diamonds. Seems like serious collectors and others do not value this jewelry type much without a fancy well known name on it. Gruens really did try to make fine quality desireable stuff.