Color variant on a Bavarian embossed stamp of the 1800's

You may have the gray blue variety. I didn't check Michel, but in Scott it would be Bavaria 42a(1876).

here's a scan of all the 20 pf stamps that I have, though there is varying debrees of "blue" nothing comes close to your gray example!

My Michel catalog makes no mention of grey blue with that wide wave watermark, which is the 1876 issue (Scott 42 : Mi 40 is only ultramarine Shades )

The only Grey blue listed in Michel is with Vertical wavy lines issued in 1881 Mi 50 which cannot be your stamp.


Has Scott got it wrong Perhaps , and possibly not for the first time . As Michel is German I'm inclined to believe them , and think again about sun fading.





stainlessb   can you check the perf and watermark on your 20pf    First row   number 3 and in the second row   Number 6  . that looks kind of greyish blue to me 


LOOK AT THIS BOOK BINDING :



Sunlight is the death of Blue !

To me, the stamp shown in the OP is Wz2 (wide wavy lines).

I checked my 2013 Michel Germany Specialized, and it lists the following shades for Scott #42 (Michel #40):

40a gray blue (first printing) [gray blue]
40b dark gray ultramarine (shades) [Prussian blue]
40c (dark) ultramarine to medium violet ultramarine [ultramarine]

The gray blue color variety (first printing) and Prussian blue color variety have noticeable premiums over the common ultramarine printing.

However, even the gray blue color variety has a very strong blue component, which is not at all evident in the OP's pics.

There is certainly a strong possibility that the stamp shown by the OP is sun-light faded, especially since it is a used stamp.

Sorry.  Depending on context, OP can stand for Original/Opening Post/Poster/Picture...

I mentioned OP to avoid confusion with the other stamps that were posted later in the thread.

Good discussion on all of this with nice contributions from Kim (khj ), Stan (stainlessb ), and Alex (vikingeck ). It's an interesting stamp and question from Henry (henrye )!

I am also a big believer in the possibility of color changelings due to sunlight, soaking, sulphuretting, and other reasons, and I realized after Alex's later post that I should have mentioned that, too. Good catch there, Alex. It's an excellent and very valid point.
Henry, in my experience, one cannot discount that sun exposure didn't happen just because it would have had to have been a long time ago.  In addition, I should add that in some cases, it doesn't take much time or even direct exposure to fade the original color.

A recent example happened to me.  I sometimes use Post-It notes as bookmarks in a notebook that I use for my work, and I had used a bright-orange color one, with just a bit sticking out from between the pages when the book is closed, about 3mm ( approx. 1/8 inch).



After just a few days of leaving the notebook sitting closed on a table in a room that does not even get direct sunlight through the windows, look how faded the exposed edge of the orange Post-It note has become.

Personally, I don't have any trouble believing that a kid long ago could have left a stamp album open in a sunlit room for hours at a time, which was cumulatively enough to fade a blue stamp to gray.  From the OP, I can't see any trace of blue in your stamp, which I also think reinforces the argument that it is faded rather than a color variety.

Disclaimer: This is just my opinion, and I am not an expert or specialist of any kind in this area.  In my experience, color changelings are much more common than rare color varieties when it comes to old stamps.