Scott 10? Deep Deep Brown Shade.... Help!

I have had this deep deep brown for some time now and always wanted to research. I have looked into Scott 10 vs. 11 but am a little lost so I thought I would ask for some assistance. The color is also one I have never seen before. I would think this is a Scott 10a but not sure. I put the 2 together to show how deep this shade is...
If pics are not good enough I will try to take more (still have not invested in that scanner).

I'm sure others will pipe in and add to this topic. The image is not that great. I know of only two way to determine if its a #10.

My 1st way is to look at the hair at the very top of the head, if blank, its a #11, see hairs, its a good chance its a #10. Then look at the outer frame lines, are they recut, if so a #10 if it has recut inner frame lines a #10A.

Then after I determine its a #10 my 2nd way is to ask someone else what they think because I'm usually wrong when it comes to this stamp.

As to the color, most likely ink oxidation. Use your specialized to see the differences I'm talking about.

Art

Shannon, it's definitely oxidized or sulfuretted. Here's a helpful cut and paste I took from USPCS's website re: sulfuretting:

"Sulfuretted" stamps are commonly advertised as #10s because of their dark appearance. Sulfuretted stamps are stamps printed with higher concentrations of ferric oxide in the ink formula that have been discolored by exposure to sulfur dioxides (commonly found in air pollutants). Sulfur dioxide (sulfide) exposure converts ferric oxide (found in Venetian Red-based pigments) to ferric sulfate (dark brown).

The image at left shows an orange brown #10 overlaid on a sulfuretted (browned) #11. Close examination of the sulfuretted #11 in the high-resolution image reveals tiny specks of original reddish ink color (arrow) in the low-relief areas in comparison to the blackened higher-relief areas of the inking. The ink used in #10 printings was not susceptible to significant discoloration from exposure to sulfides, although many #11 inks were.



Hope this helps-- Ray

Art & Ray,
My most sincere thanks... I am once again humbled with your knowledge and willingness to help.