How do you tell if paper notes are counterfeits? I'm sure if you send it off to be graded, one could find out that way. And, I've been comparing photos of known authentic notes to potential purchases. But, this has its limits. Is there an online resource that goes deep into what to look for in world currencies? For example, if I wanted to check up on some Reichsbankmarks from 1923, what would I have to look for in particular? Or, how about the Pengos from Hungary in 1946? I doubt that they counterfeited the hyperinflation currencies at or close to the time of issue, but I'd imagine that counterfeits can be easily made today. Thanks in advance.
