Russia Sc#201 Overprint Question

How do you distinguish between the Typographic and Lithographic surcharge indicated in the catalog for the SC#201 model?

I have these examples, which I can distinguish as follows:
-In the first line, two SC#201s and one SC#201a. The overprint on the first two is strong, and I assume it's also lithographic. The lithography on the last one is less strong, and it's clear that either it was struck twice or the ink moved over the 7 and 5. Perhaps typographic?
-In the second line, one SC#210 and one SC#210b. The overprint on the first one is stronger and more perfect, although the second 0 has a small error at the top inside; I think it's lithographic. The overprint on the second one is weaker, and the first 0 is incomplete. Is it typographic?

For the sake of discussion, I'll add what I think Lyapin's catalogue says about the March 1922 stamps (7500p, Sc201).

The surcharges come in two types, Type 1 being 23 to 23.5mm in length, and Type 2 being 24 to 24.5mm in length, and in two colors, black and black-blue.

Both types are found in black on all three paper types: ordinary, thin and chalk-surfaced paper.

In black-blue ink, only Type 2 (long) is listed for ordinary paper (with a significant CV premium). Black-blue ink isn't listed at all for thin paper, and both Type 1 and Type 2 are listed in black-blue ink for chalk-surfaced paper (with a very small premium).

So, the big find appears to be a long surcharge in black-blue ink on ordinary paper.

I think it also says that the surcharges were set up and printed 25 at a time, 5x5. It would make sense that there could be some variations in the surcharges.

They all appear to be typographic. If you zoom in you can see a faintly heavier outline of the letters than the body of the letters. That is characteristic of typography. Also, on mint stamps you may be able to see an impression (indentation) of the overprint on the back of the stamp.

Lithography is a surface printing technique so there will be no heavier outline; it will all be the same uniform color. On mint stamps there will be no impression of the overprint on the back.

Could it be that the type I and type II references, due to their length, could refer to typography and lithography? I say this because it would be a good trick to distinguish them...

I have 2 copies of Russia Scott 210 both mint hinged.
The overprint on the right is obviously much more solid.
Now on the back I see a very slight indentation (impression) of the numbers when
I view the stamp obliquely against the light.
This would steer me towards typography printing for the overprint.
For the one on the right I see no indentation which doesn't necessarily
make it a lithographic overprint either.
IMO both overprints are via typography printing.



@Murasama if yours are mint what does the back show?

The reverse looks like this...



This doesn't look easy at all...
In the first line, the first two are chalk surface and probably lithographic, I think this because it's very marked and uniform, with no noticeable differences between the stamps. Furthermore, no trace is visible on the back. The third is more complex; it's made of pelure paper, and the overprint doesn't seem as strong as the previous ones. In this there was an error with the ink or with a double tap (I don't know if this can happen with both lithographic and typographic printing). It shows on the back, but of course, the paper is very thin... Typographic, perhaps?
In the second line, the first one is plain paper, with no marks on the back... but I have no idea what it could be. Typographic, perhaps? The second is made of pelure paper, and the printing is uneven with flaws and marks on the back— typographic, almost certainly.

The Zagorskiy catalogue mentions a lithographic surcharge on the 7500r/250r (Sc201) only for the blue-black diagonal surcharge. It also refers to the horizontal surcharge variety as exclusively lithographic.

@vasia, any chance you can show a scan of Scott 210 in the Zagorskiy catalogue?