Peru Sc# 1873, Fake Canecellation?

Since the cancellation is partial, there is a good chance an expertiser cannot or will not confirm it is genuine.

I think the same thing...it can be intuited based on many small details, but it is difficult to certify in one sense or another with complete certainty. If it's a fake, they set the bar very high and complex...

"Naturally I would like to know If the cancellation is original, but not because of the economic value, but out of pure curiosity and evaluating my own criteria..." - Even if it was for economic value that would be okay too. Many posts on message boards virtue signal that something is not for economics or money. And that may be true in this case, but one does not have to mention it because it does not matter whether it is or is not. Just my2cents. You have a nice stamp. I agree with the others to get it certified and use the PF or APS.

You like it. You aren't planning to sell it. Why would you pay for a cert? Unless you are deeply invested in having a cert saying, "Genuine, used" and you would keep buying examples until that happened.

Each person figures this out for him/herself, but if I thought I had a genuine stamp and I didn't know about the cancel, I would tuck it away and be happy.

In short, I like your stamp.

My 2d.

Because if you don't really care if you have genuine items than why not fill your collection with cutout auction catalog photos? From the beginning collectors have expended enormous energy on research and keeping "album weeds" out of their albums. Has that changed now? Willful ignorance is maybe not the best approach to philately.

Context, good sir. Context.

I think some readers especially new readers don't understand my posting on the first page here . When I stated I am 75% sure it is real ..Does that mean it is real ---yes but I would not issue a positive CERT . for it , it is still questionable .

This is more common than you think. Not enough information to be positive or negative to the stamp.
This is 2025 and this stamp has been around , so I am thinking maybe a cert. has been issued before ,so the first place to start is check for a previous issued cert.

If that stamp from a former Spanish colony has been lying around in Spain for decades, you are not going to find a paper trail.