Has anyone ever heard of a misprinted page of Canadian Stamps from 1970. I believe they are Scott Canada #507.
I haven't been able to find any record of them, other than that my Dad is keeping his sheet in protective plastic at the bank. He has another full sheet of the same stamp without the mis-print that he has mounted in his albums at home. How would I determine what this is and what it might be worth? Authentication? How do you get it done?