Confirmation On Scott U493A Please.

I think I have this one pegged as a U493a which would mean Die 2. It is a nice blue paper which doe's not appear to be laid paper.
Am I right? Also some green ink on back which I am not sure about.

Defintely NOT a U493a (wrong image type).

I think it's probably a U495 or U498a (Die 1)...(Word "UNITED" nearer inner circle than outer circle), but can't tell for sure, as based on the image provided I can't tell what color paper the cut square is on.

If it is indeed on blue paper as you stated in your original comment, then I think it would be a U498a.

I agree with wt1: if the paper is blue, then it is a U498a.

The marking on the back is a collector's mark (usually a collector's initials). In the early 20th century (maybe even back into the 19th) it was common for stationery collectors to have a rubber hand stamp with which they could "brand" their stationery. There are a variety of opinions as to whether these are undesirable or not. Certainly, if on the front, they would be undesirable. For some collectors with philatelic gravitas (Barkhausen, White, Maisel, etc.), it can be considered a plus as far as expertization goes.