The Dolphin - SEIKO World Time
Model No. 6217-7000
The Dolphin Case SEIKO World Time was a limited production run in December of 1964.
After the Olympic games in October of 1964 SEIKO halted production of the Olympic torch case back, replacing it with this new etched dolphin case back. The dolphin logo can be found on other SEIKO watches of the time. It was generally used to signify that a watch was waterproof, in this case to 30 meters.

Estimated Production
Based on the data collected to date, these "Dolphin Case Backs" appear to have been manufactured in December of 1964 only.
The 7-digit serial number scheme would allow for up to 99,999 of these watches in that month, but the highest cataloged number is 9,306.
It seems likely that there were around 10,000 of these watches produced in total.
Click here to view the cataloged examples.
The Case Back
The dolphin was etched, and like the etched Olympic torch case backs, many have been worn down or worn away completely.
The placement of the Serial Number, and the fact that no other 6217-7000 World Times were produced with a serial number starting in "4D" make it easy to identify these watches, even if the image of the dolphin has worn away.
Note the higher placement of the serial number on the Dolphin case back vs the Olypmic Torch version.


The Dial
Examples of both silver and black dials exist with 87.5% in silver and 12.5% in black.
This watch is otherwise identical to the original 6217-7000.
The GMT Hand
Of the cataloged watches, all with black GMT hands are of the thin variant.
Two examples have red GMT hands.
It is not clear if these are original to this watch.
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