Mexico Stamp 10 C Different Colors

Dear Firends

Kindly I need your advice about the attached stamps , is there a different in color or its normal case ?
Note : year of printing stamp 1899 - Mexico

A quick look at my Scott listing for Mexico produced no mention of the single color for this issue. Although Scott is not the definitive authority for Mexico I suspect it is color changeling maybe chemically altered in some way. But I could be wrong. Wolf-==-

Many thx sir

Most definitely a color changeling from oxidation. These are two colors that happen to be vulnerable to color changes.

There was a second printing, but that was also a bicolor, blue and orange. Based on your postmark date (if I'm reading it correctly), yours predates the second printing, so it is violet and orange in Scott. Yvert lists it as violet-brown and orange.

Violet is often subject to fading with soaking, but with the change to the vignette, too, I would go along with oxidation. If you have hydrogen peroxide available to you, just for fun you could do a short soak, followed by a freshwater rinse, to see what happens. Start with 30-45 seconds. You might brighten up the vignette. I honestly have no idea what will happen to the frame.

It's not "worth" the effort, in any traditional sense, other than for the sake of experimenting.

Rather than a soak, set something to support the stamp above bottom of a closeable container, dip a q tip in the Household type hydrogen peroxide, cut the wet tip off, drop in in the bottom, place stamp face up on support, close container overnight. You won't risk the frame ink this way. This method works without disturbing the gum on mint stamps.

Here is what I use, an old pill bottle and an empty 250 meter spool of Guterman thread, I glued the spool in place.