France #102A But Wrong Color

I have what appears to be a France #102a (violet on yellow paper) but the stamp color is wrong. It is 75 centime, type II, perf 14 X 13 1/2, no watermark. The paper looks yellow rather than orange, hence my inclination towards #102a. But the stamp itself looks green rather than violet. I included a scan of both this stamp and a #102 (violet on orange paper) next to it so you can compare the color from my scanner. Any idea why the color is green?


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The usual suspects are light or chemical damage.

Search this forum for "colour changeling" or "color changeling"

Rod, Thanks for the tip. I found an article on color changelings and discovered that violet can become blue or occasionally green when the red is removed. Even found one similar example of just such a color change among the illustrations.