An approximate table of Zenith movement serial numbers and their corresponding years of manufacture.
It isn’t always possible to determine the exact date on which a watch was produced, because movement stock could often lie in warehouses for several years before being inserted into the case (in practice, there was a difference of 20 years). Below are two variants of the serial number tables. They more or less coincide, with the spread being plus or minus 3 – 4 years.
The serial number is located on the movement of each watch.
Table 1:
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Table 2:
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ZENITH Movement Calibers – Production Reference Table By Year:
Translation: ‘Caliber’ – ‘Start of Production’ – ‘End of Production’ – Circulation (pieces)
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