This is an obverse die trial, in white metal, without date or dentilation. Judd lists this under 1850 whereas Pollock lists this under 1859.
The piece appears to have 1850 written where the date would appear. The image is not strong enough to see whether the I in Liberty is a second L or was struck over a second L as on pieces dated from 1850-1858 or an I as on 1859 and later. Click on the thumbnail image for an enlargement and see for yourself.
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 #36.
Photo courtesy of the Library Company of Philadelphia.