Thanks go to Kohei for this.
Vintage Seiko movements can often be found in a "plain" steel finish, or in a (normally, yellow) gold [or just gold colored??] finish. I assume the plated movement is a somewhat "premium" product that may go with the "luxury" or higher priced models of the watch using that calibre movement.
Now, a twist!!
I recently came across an old Seiko Marvel 14021 ca. 1956 (discussed on this very forum a few weeks ago!!) that had a coppery colored plating on the movement, like many old Omegas. Note that this movement is the one PRIOR to the use of the 5740 series, something developed out of the Seiko Super of the early to mid '50s. I thought nothing of the different color back when it was up for sale, just figured that Seiko switched to the yellow plating later on. BTW - I've also seen a copper colored Marvel movement pictured on an article on GMT+9 [RE: Marvel, Super, Unique; watches of the 1950s]
In addition, the balance assembly looked "jury rigged" - unlike any production shock protected Seiko balance of the period (or later).
Well, I came across this little bit of info yesterday written by Kohei in another venue:
"There were copper red plated version existed too, but NOT supposed to be FOR the RETAIL, Seiko only provided these red plated movement watches to the their watchmakers for testing of assembly skills (so they cannot cheat by swapping the movement).
Sometimes showed up for sale by the watchmaker whom kept their watch."
Ed. Note: Capitalized words in the quotation are mine for emphasis, not capitalized in original text.
In another location he indicated the test was of applicants to a job position (I assume, with Seiko itself).
Hmm!!! Sounds like I "found" (but, didn't buy) one of the old Seiko "test" watches. That may also explain the difference in the balance assembly - if a watchmaker applicant kept the watch & used it to "practice on", he may have done some "advanced surgery" on his test piece either to learn more techniques or get knowledge of different kinds of balance assemblies (non-Seiko??). Or maybe... the balance assembly was some Seiko internal "experimental" model or...??? Lots of conjectures come to mind...
Rather interesting to think about!!
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