Watermark Values Question

I am curious as to which series of stamps are the most valuable
based on watermarks ....I have many small envelopes full of duplicate stamps, and understand that the only difference between them might be watermarks. could someone point me in the right direction to a source of value based on watermarks? US as well as world.
thanks
David

That's sort of an open ended question and hard to give any definite answer.

If you mean the Large banknotes then it's paper type, watermark, perforation count, or the design elements (eg: secret marks) Or....

You could be talking about the small banknotes which either have a watermark or don't and that only applies to the ones with the "triangles in the upper corners of the design and which type of triangles they are type I.,II. or III. ...?

If you mean the Washington Franklin series then there is quite a bit more to it than just watermarks. It comes down to IF there is a watermark and if there is, then which kind (wmk 190 single line or wmk 191 Double line)? and then, there is perforation count, and if you get that far then, there is which type (I.-VI.), and even then it depends on plate state or the printing plates condition; and even which kind of press is involved in printing your stamps (eg: Flat plate, rotary, offset...) if you can even make all that stuff out because it just printed a few million of them!

What I'm getting at is there need to be more general information about which "set" you are referring too?

I guess I was being lazy....i was looking for a general "point me in the right direction."?
Hopefully, assuming that the areas that might be fertile hunting grounds are the bank notes and washington franklin series?...

Of course, if you're talking about a different country, I've found that Great Britain has a bunch of different watermarks in different orientations that make for some fun searching. Most are pretty common, but some sideways versions are worth a pretty penny. Then there are the ones with just one subtle difference in only one area that make the whole search worthwhile. I don't have any of those, but keep searching...

interesting pioint off topic...i just googles...valuable Great Britain stamps watermarks...and this thread popped up second in the list?....that was quick