Beginning in the mid 1990s, with the advent of e Bay and other online venues, collectors have been able to piece together additional dating information through the posting of individual vintage advertisements.
All of which has resulted in a greater refinement of the original "Cleves Chart." (And that effort continues.)The past two or three years have yielded more tools for collectors to work with, but the results of all these efforts have proven painstaking and piecemeal at best, as information and clues are scattered among a variety of paper publications and online resources, the latter of which must surely put the number of sources into the dozens if you count discussion websites.
By studying literally thousands of Gruen watches, and developing techniques for dating and identifying model names (and recording every detail about each watch) we believe we have reached a significant breakthrough that will help Gruen wristwatch collectors more definitively pinpoint the age of a given specimen.
Enter your Style Number in the box below to find your watch's date and additional Style Number information.If you want to learn more about the application of Style Number Dating to help understand when each of Gruen's movements went into production and stopped being used in production, check out the analysis of in the Reference Section.It's a visual view of each movement's use of Style Numbers. It shows how many Style Numbers were associated with Caliber 311 movements and what years those Style Numbers represent.Case Manufacture Date - This date tells you when your specific watch's case was made.Out of all the dates you can find on a watch, this is the date that determines exactly how old your watch is.
You want to match the date with the correct use of that date.