What Makes a National Bank Note Valuable?
The most important trait a national currency note needs to posses to be valuable is that more than one person really wants the note. That sounds obvious and it is… but demand drives price, end of story. For example, you have a note from a bank where there are only three known and one is yours. You might think it’s a priceless rarity and it could be. But the fact that there are only three known isn’t enough to know if the note is special. If your three known note is from rural Pennsylvania you may find that no one cares and the note isn’t worth more than a few hundred. What you need is the situation where more collectors need the note for their collection than the market can satisfy. If that same hypothetical three known note is from a state like Alaska where the demand is endless, you have a great note and collectors will be very aggressive in their offers.
To summarize, the value of a note is driven by collector demand. This is why valuing national bank notes is so interesting. It comes down to market knowledge and even with superb market knowledge it’s easy to over pay for a note.