How to distinguish dirty green papers from real dollars?
There is such a profession - to detect fakes. And the book by Alexei Masich, an expert on this topic: "US Dollars: Genuine or Fake?" answers this question.
Spoiler: "There's no way to tell the difference."
Before you start checking your dollars from the stash for authenticity, you need to understand that fake dollars experts divide into two categories: superfakes and ordinary fakes.
Super forgeries by the parameters of the main elements of protection practically do not differ from genuine money tickets. They can be classified by experts as counterfeit only by minor defects of printing plates, which are reflected on the imprint.
As I understand, it is impossible to distinguish a super counterfeit from a real bill. Yeah, what's the point? If you can't tell the difference, neither can another person. Money acts like money because it's a highly protected object. And for ordinary people there is no difference, as it seems to me, what they deal with, what printer these bills came from, if they are accepted everywhere (for example, in Cuba they take any dollars of any years).
Super forgeries are the domain of experts and the government. I emphasize to you that counterfeiting of bills is prosecuted and entire services deal with it. Towers! I've seen some of their work. I'm impressed.
I doubt you would use a book like "US Dollars: Genuine or Counterfeit?" to authenticate the bills you have in your possession. You got them through the bank, and there they were studied by knowledgeable people.
The author writes that strangely enough, for most cashiers, the main way to authenticate US money bills is usually by visual examination of the main images. This is usually accomplished by using the portrait (portraits of dead presidents) and the frame fragments on the face of the banknotes... For example, in the portrait, such defects can lead to distortions in facial expressions, expressions of gaze, etc., which is detected by specialists during the visual inspection of banknotes.
That is, if the American president looks at you with a smirk, it makes sense to doubt the authenticity of the banknote. If you want to fret and spoil your mood from the fact that you find a fake at home, then read the book "U.S. Dollars: Genuine or Fake?". It's short, illustrated.
Know that such literature on bill authentication exists.
P.S..
In the description of the book on the website of its publisher:
К. Clifton, Resident Agent in Charge of the United States Secret Service
"...We are familiar with your publications. We would especially like to note the reference edition by Mr. Alexei Masich "US Dollars: Genuine or Counterfeit?", it provides quite detailed information on all varieties of super forgeries. The US Secret Service has nothing to add at this time"
All the best
