Again.. couldn't find as much info on fakes as I'd had liked. My spidey sense is already tingling with some pieces. More later.
For the Seebeck 1879 and 1880, I checked the stars per Dieter Bortfeld. I don't know if that's enough but I guess is something. They'all look like this:
Not a clue about the rest... I guess I'll need to check for the watermarks?
I think I need to calibrate my scanner... or my monitor... Or both. Or probably just stop procrastinating and finally get Lasik on my eyes. The two bluish stamp at the bottom are actually dark blue and purple.
I've many doubts about the values of the following pages. I found exactly zero about them but the other copies I have show important differences in the design and quality. I don't know what to think about them.
These are the other copies I have, that shows important differences with the ones on the page. I don't know if they are just other types, varieties... or anything else:
As usual... any information about these pieces is highly appreciated!