Dating elgin wrist watch
For example, movements made prior to 1924 do not bear the standard movement date code found on watches dated 1924 through 1949.
(For a list of those codes, visit Bulova Date Codes.) Additionally, the case serial numbers on those early watches tend to begin with "1" or "2" and appear to bear no correlation to the date the watch was made.
I have recently begun to develop a theory regarding certain "markers' that may help us identify the date--at least with a reasonable degree of certainty--of these very early watches.
So, the lists may be incomplete and even inaccurate to the extent that they contain information on movements that are not on-hand and available for examination and verification.
Co." on the movement, and with an "American Standard" only case signature, pre-dates April 1923.
Narrowing down the date beyond that with certainty may not be possible based on current information.
At that time, Bulova started using with regularity standard date codes on the movement.
Additionally, in many instances, the case serial number on these later models can be used as a date reference.
For a detailed analysis, and examples, of Bulova case signatures through the years, Bulova Case Signatures.