Omega 2791: two-tone black dial from the 1950s

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This is a recent arrival for me. It's an unmarked Seamaster with a two-tone gilt dial from ~1954.

The inner dial is glossy black, with some flaking that reveals the gold/bronze color below. The outer dial has a matte black finish. Depending on the viewing angle, the dial contrast can be subtle or rather apparent. It makes me think of the night sky, as viewed through an aperture.



It's interesting to read about how these gilt dials were made. As I understand, the features were printed on a base metal (e.g., bronze) using clear lacquer, and then electroplated with black paint. I'd be curious to know how they made the small seconds cross-hair, which crosses the glossy/matte boundary. Perhaps there were multiple masking stages, or it was printed on top. I'll have to look more closely.

It runs a 30 mm movement (cal. 266) and has a 36 mm case.



I was hoping to solicit some advice. The hands show some grime or damage. It may be some remnants of epoxy (or some such material) that was used to stabilize the hand lume. Would you ask for a gentle cleaning of the hands during service? I'm fine with the lume as is, but wondering if it's worth trying to clean-up the hands a bit.

Finally, cheers to those who manage to do a good job with black dial photography. My wife wants to know why I had to take so many photos of the same watch.

 
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I kept my hands normally aged to match the dial.

ref 2577 circa 1954
 
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I kept my hands normally aged to match the dial.

ref 2577

Possibly a 2576, as 2577 would be a center second?

If you trust your watchmaker, I'd ask him to check the residue under the microscope and let him decide if he considers the removal of the grime to be relatively risk free. If so I'd give him the go. Nice piece!
 
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You can certainly have the hands replated and relumed if the residue/grime can’t be otherwise removed without damage. I’ve done that with several vintage watches and the results were excellent.
 
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MtV MtV
Possibly a 2576, as 2577 would be a center second?

If you trust your watchmaker, I'd ask him to check the residue under the microscope and let him decide if he considers the removal of the grime to be relatively risk free. If so I'd give him the go. Nice piece!



I think GG, himself, swapped the backs at the Factory, liked it, and let it slip out as a Prototype to be discovered by a thrilled collector 50 years later.😁

or


Some WM replaced a damaged back and the customer was happily, and blissfully unaware.


I was just happy to find an early 1950's unlumed black dialed cal 344 in pretty good shape.
Edited:
 
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I think GG, himself, swapped the backs at the Factory, liked it, and let it slip out as a Prototype to be discovered by a thrilled collector 50 years later.

or


Some WM replaced a damaged back and the customer was happily, and blissfully unaware.


I was just happy to find an early 1950's unlumed black dialed cal 344 in pretty good shape.

I'm sorry 🤦 You're right though, it does look cool!
 
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MtV MtV
I'm sorry 🤦 You're right though, it does look cool!


Collectors are cool, and, speaking only for myself, completely nuts😁
 
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@__ryan__ Cool watch and dial, thanks for sharing.

I could be wrong, but I believe that most watch dials from this period were made of brass (copper and zinc) rather than bronze (copper and tin).

As for the matte and glossy finishes, I have a vague recollection of reading that these can be due to the lacquer that is used on the surface of the dial.

One intriguing feature of your dial is that there appears to be much more deterioration on the glossy central portion than on the matte outer portion. It looks as though the deterioration consists of damage to the black layer, which has revealed the gold tone underneath. It would be neat to see macro shots of the intersection of the matte and glossy portions from different angles to compare their appearances.

I would guess that the cross-hair was "printed" prior to the the application of any surface coatings. I do not know how specific portions of the dial would have been masked in order to apply coatings selectively.
 
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Thanks for the input. 😀

I think I'll have a watchmaker take a look and see if some cleaning is possible. I can appreciate the appearance of the hands and lume as they are, and I'd rather not get into more substantial changes.
 
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I could be wrong, but I believe that most watch dials from this period were made of brass (copper and zinc) rather than bronze (copper and tin).
You're probably correct. I tend to forget that brass and bronze are different alloys; they're just one thing in my mind. Whomever did the naming really missed an opportunity: bronze should should have zinc (Zn) as the alloying element, and brass should have tin (Sn).

One intriguing feature of your dial is that there appears to be much more deterioration on the glossy central portion than on the matte outer portion. It looks as though the deterioration consists of damage to the black layer, which has revealed the gold tone underneath. It would be neat to see macro shots of the intersection of the matte and glossy portions from different angles to compare their appearances.
That is indeed the case. The photos above have pretty high resolution, but I'd like to get set up for macro shots at some point. That would be a cool thing to photograph.
 
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Whomever did the naming really missed an opportunity: bronze should should have zinc (Zn) as the alloying element, and brass should have tin (Sn).
Agreed!

EDIT: I was thinking that, if you did take some macros of the dial, it would be neat to see if there is any difference in the appearance of the printing on the matte vs. glossy parts. This might help to determine if there is a difference in the surface coatings on the respective parts of the dial. Different parts of the cross-hair would be neat to see, as well as the "Swiss Made" printing versus the "Omega" signature, for example.