Upper Silesia Plebiscite Overprints - Dealer Marks

I recently got these Upper Silesia Plebiscite overprints, and on the back, two of them have dealer/collector hand stamps.

Anyone recognize them? I can make out "Muller" and "Schultz"

The mark belongs to Dr. "Harry" Leobschütz Müller.

It is mark known to be forged. The mark on the back of your stamp is too unclear to tell, which probably means the mark is a forgery.

They picked the wrong mark to forge. Dr. Müller's "expertise" is considered questionable, so even if genuine, the mark is not considered reliable.

In my Michel Deutschland-Spezial, there is a warning about this mark.

Thanks K. I wonder why would someone forge such a mark on stamps of minimal value?

For practice? To create a small lot with a forged stamp and a few genuine stamps, all bearing the same mark?

Were the stamps genuine, they would NOT be of minimum catalog value.

If the overprints were genuine (and they are not), it puts the stamps in the $10+ order of magnitude for catalog value.

Were the postmarks also genuine contemporary use (and I don't think they are), you will notice they were canceled on the first day of issue and that would add an additional significant premium. Fake cancels are plentiful for this issue.

Thanks for the info K.

I realize the three stamps catalog about $10 each as used stamps (I paid a couple of bucks for the 3). I consider $10 "minimal" when it comes to fakes. $10 is my stopping point for minimal though

How do you identify the overprints as fakes - I don't have any others for comparison.

As for the postmarks, careful examination shows that they are ON TOP of the overprint and that the Oppeln type and ink quality is the same of as other Opplen cancels I have on much cheaper Upper Silesia stamps.

Edit: When I get home I will post a higher resolution scan of one of the overprints.

Genuine overprint device was used to make the fake overprints. See how worn the overprint looks, especially the numbers. The forger was really pushing the device to the end of its useful life. It is merely my opinion that the overprints are fake. I am not an expert, but my conclusion is based on what I have seen in the past.

Likewise, genuine cancellers used to cancel the stamps. On most genuine postal cancels (not philatelic, not favor cancelled...), the ink is oil-based and spreads out, often resulting in a blurry appearance and unsightly blotches. That doesn't mean there were no clean cancels (genuine clean cancels are the exception, usually philatelic or favor cancelled), but the great majority of clean cancels are NOT genuine. Philatelic covers of that era are an example/exception of clean cancels achieved by using a different ink. On most of the genuine cancels, they are seldom well-centered and usually off-rotation significantly. If well-centered and not rotated, most genuine cancels will still show signs of ink spread unless they were very lightly cancelled.

Cancel on top of a fake overprint means the cancel is also fake.

Warning signs of non-genuine cancels:
-- all have the exact same date/time/ID stamp
-- all oriented at approximately the same rotation
-- all pretty clean, no blurring/blotching

These are generalizations, and there are always exceptions.

If you've ever noticed the blurry oil-based ink cancels, you will know what I am talking about. All those pretty "on-paper" cancels that you see, 99% of them are fake. Insist on seeing the full cover. Otherwise, just a forger technique of sticking stamps on paper, cancelling them, and then cutting them up into individual squares.

Great information K! So it would appear I have a triple forgery: Fake overprint, fake cancel and fake collector's mark!

When you say fake cancels, are you refering just to Oppeln, or the other towns also? Many other one were shown here, which you probably saw (most are nice clear cancels):

https://goscf.com/t/14537#14537

Here is a closeup of the 10pf, and another "greasy" cancel I have on an official; in your opinion would that appear to be genuine?