This is a reverse hub trial, in lead, of a heraldic eagle. It was not used on any patterns that I am aware of. It is possibly the work of Anthony C. Paquet but this is uncertain.
For additional information on this, please refer to the article on the 1861 Paquet dollars in the ANA Centennial Anthology.
The piece is unique and is ex Nagy, Judd, Kosoff-Bowers and Merena 11/85, Heritage 10/94.
Photo is a scan from the Bowers and Merena Kosoff sale.