This is a reverse die trial of the 1866 with rays nickel 5 cent pattern used on such patterns as J416-J417/P488-P489 and also J497-J499/P584-P585 among others. This was listed as JA1865-2 in the 8th edition of Judd.
At least 2 are known and both are illustrated above. The color example, on a normal diameter planchet, was part of the materials purchased by the Library Company of Philadelphia from Maxwell Whiteman. It is listed as inventory #6.
Photo courtesy of the Library Company of Philadelphia.
The other piece, on an oversized planchet, is ex Kosoff 3/42, Auction 89, Dr. A. Roter and the illustration is a scan from the Auction 89 catalog.