If they are not stored in a sealed container with silica gel packs they will tone. Humidity is the culprit.
Very nice reverse but the obverse would limit it to F 15 I'd say.
This should help - Click Here
Only to some people - to others it is meaningless.
Just curious, what did the cataloger grade the coin in the B & M sale ?
I'd check Heritage for values. The BG numbers were created by Breen and Gillio who have documented the entire series of California Fractionals.
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