This is an incomplete obverse die trial, in white metal, of the shield nickel design used on J416/P488 prior to the addition of the date and dentilation. This was listed as JA1865-1 in the 8th edition of Judd.
Regrettably, it is badly corroded.
It is believed unique and was part of the materials purchased by the Library Company of Philadelphia from Maxwell Whiteman. It is listed as inventory #4.
Photo courtesy of the Library Company of Philadelphia.