The regular dies trial piece in aluminum, one of about a half dozen known.
These were deliberately struck to show how easily aluminum coined and for sale to collectors in cased sets several of which are still in existence including the former Garrett set and one in the Eric P. Newman collection. Virgil Brand owned 2 sets - Woodside's and Stickney's. To view the set, click here.
An example is also listed in copper J635/P707 but is unconfirmed. A shield nickel of this year is also known struck on a cent planchet. For more on this, click here.
Photo courtesy of Bowers and Merena.