Curious On Value Of $20$

to the CCF

john100 is right, the prefix 510 is a replacement note.
Too bad about the condition but it still should be worth well in excess of $100. 00.
In uncirculated condition it would bring $500- 600.00.
These values are in CDN dollars.
I would send it off to be graded as this would help in determining the value.

From. the scans (the wear on the reverse central-vertical fold, uneven edges & blunted corners) I would estimate your note to be no better than VF condition. This is from eye-balling the scans which is not the same as being present to inspect your note via a light-box (which is what BCS would do).

My 2019 Charlton puts this note (BC-54aA) at $225 for VF so it may be worth a bit more but difficult to say as the 1979 $5 & $20 replacements have not been very popular. Not entirely sure why except perhaps there were way more of these floating around for several years with the BIRDS series (rather than the 1969 version which it replaced). It was the first time the SN were moved to the back & it had some pink added to distinguish it from the 1973 $1.00 (seniors were getting the two mixed up).

Having said that, the "Lawson-Bouey" 1979 replacement was the first (3.2M printed) of its kind & caught most collectors off-guard (as we didn't know the significance of the "510" for replacement function until long after its release) & thus commands the highest BV in UNC $750 & $1000 in Gem Unc. So it's a good (tough) note to have.

Congrats!

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