This is a complete reverse die trial, in white metal, of the regular double eagle design used from 1850-1865.
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 #39.
An example in copper is also known. It is from the Eric Newman collection and has been graded NGCAU50. This would be JA1849-5 if it is indeed genuine. For more on this piece, click here.
Photo courtesy of the Library Company of Philadelphia.