An unusual overstruck U.S. copper pattern was recently identified by numismatists at Numismatic Guaranty Corp.
The pattern is an 1870 Standard silver dime design featuring Liberty with a cap decorated with three stars, over an undertype that is also an 1870 Standard silver dime design featuring Liberty wearing a tiara without stars. The pattern is struck on a copper planchet.
“Standard” refers to the word at the top of the reverse design on both pattern design types.
Graded Proof-64 Brown, J-839 over J-845, the description refers to Judd numbers, which are reference numbers taken from United States Pattern Coins, Experimental, and Trial Pieces by J. Hewitt Judd.
Consisting of more than 200 different issues, the Standard silver pattern series was struck in both 1869 and 1870 and included three different Liberty head styles in dimes, quarters and half dollars. They were struck in silver, aluminum and copper, and came with reeded edge and plain edge. Other alloys and variations do exist, according to NGC. They were made expressly for collectors who purchased them in sets from the Mint. Cloaked in mystery, no production records were kept, according to NGC.
As for this overstrike, there is speculation, according to NGC, that an example of the J-839 was needed to complete a set. However, none was available, so the J-845 design was overstruck with the J-839 pattern.
According to the Judd text, only four to six examples of the J-839 are known, while an estimated seven to 12 examples of J-845 are known.
Rarely are overstruck patterns like this identified, according to NGC. However, this is the second discovery NGC has made this year. Check ngccoin.com.