519 - Missing Colour Or Changeling

Hi,

The red colour appears to be missing on the right stamp.



I thought it could be the result of light exposure. After a 4 month of daylight exposure on my office window, the red is still there, but the yellow faded away. Any comment on the missing red would be appreciated.

Hi Major1044...I would think it is caused by sun or light exposure..Notice, all colours are affected...As a printer when I was young, getting the exact same colour on a separate run was almost impossible...My opinion is light fading...

Robert

Thanks for your comments Wert.

I should have mentioned that the top stamp on the left is of normal colours. However, there is absolutely no red on the upper right stamp. What appears to be reddish is in fact of orange colour. I don't think that the sunlight made the red disappeared. In this case, the bottom stamp indicates that only the yellow faded away due a long term daylight exposure. Now I was wondering what else could have made the red completely disappeared, if this is the case.

Try experiments with different lengths of soak times in tap water with chlorine?
Don

You do not say where this stamp came from. It may have been exposed to some atmospheric contamination either an oxidising or reducing component accidentally or on purpose. It would all depend on the actual chemical composition of the colours and that is probably not known.

AQ

Is orange not a combination of red and yellow? Could it be that the red plate was under inked? Just my two cents,

Peter

My Unitrade says this was Lithography, with 4 colors. Extreme closeup of the buttons in my used copy reveals:

Magenta
Yellow
Blue
Black

If the red (yellow + magenta) is missing, then what makes the buttons different colors, as shown below?



I'm not a color expert, so a closeup of the questionable areas would help me a lot.

I checked a mint example and agree with Partime. The red colour is present - it is a different shade. The cause? Who knows, perhaps chlorine like 51studebaker said, or some other chemical. Major 1044 pretty well ruled out light, as that removed just the yellow colour.

Hi Partime,

Hereunder is a close-up of the stamp being questioned.
This is the best I can do.