This is a reverse die trial of the 1866 with rays nickel 5 cent pattern. It is not the one used on such patterns as
as it lacks the center dot so obvious on those patterns.
It is actually the reverse die used on the regular dies trial pieces
. According to Kurt Brintzenhofe, the die trial is
"reverse style B (Flectcher hub I) with the star at "ES" of STATES pointing to the "E" instead of the "S" and the star centered over the "T" in Cents instead of over the right side. That places this as a circulation/business die for either 1866, or business/proof 1867 with rays die"
This die trial was listed as
in the 8th edition of Judd.
At least 2 are known and both are illustrated above. The example on the normal diameter planchet was part of the materials purchased by the Library Company of Philadelphia from Maxwell Whiteman and is listed as inventory #6.
The other piece, on an oversized planchet, is ex Kosoff 3/42, Auction 89, Dr. A. Roter, Rau-Heritage 4/18, K. Brintzenhofe - PCGS64.
Photos courtesy of the Library Company of Philadelphia and Heritage