Arthur, do you know anything about 1957 Silver Certificates with duplicate serials? More specifically, was there any overlap in the serial numbers between 1957 and 1957B? I don't know much about the numbering of American notes but I thought that the numbers only reset between major series changes (like 1935 to 1957) but not between 1957 and 1957A or 1957B. However, I might be mistaken about this.
Sorry, I have not seen or heard of duplicate serial numbered notes for the 1957 Silver Certificates. A very large number of these notes were printed (in the billions) and I am not familiar with the exact numbering system they used.
Here’s a breakdown on how many 1957 $1 Silver Certificates bills were printed by type and signatures:
1957 Priest / Anderson — 2,609,600,000 (that’s over 2.6 billion)
1957* (Star Note / Replacement Note) Priest / Anderson — 302,400,000
1957-A Smith / Dillon –1,594,080,000 (more than 1.59 billion)
1957-A* (Star Note / Replacement Note) Smith / Dillon — 92,320,000
1957-B Granahan / Dillon — 718,400,000
1957-B* (Star Note / Replacement Note) Granahan / Dillon — 48,000,000
The only production/printing errors that I have seen on the 1957 $1 Silver Certificates are:
Inverted Serial Number
Offset Printing
Mismatched Serial Number
Stuck Digit Error
Cutting Error
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Arthur Richards
Contributor, Charlton Catalogue of Canadian Government Paper Money, 19th, 20th, 21st, 22nd and 29th Edition
Pricing Panel Member, Charlton Catalogue of Canadian Government Paper Money, 21st Edition 2009