The famous G*W.Pt. (George Washington President) Birch cent. It is also listed as Baker P-37.
An article by Carl W.A. Carlson in the March 1982 edition of the Numismatist describes this as being the original Birch die. It was later modified to produce the more common Birch cent J3-J5/P4-P6.
Only a single example, struck in white metal is known. Its pedigree is ex-Sotheby 3/1888, G. Bascomb (H. Chapman 1/15), Garrett-JHU, Bowers and Ruddy 3/81 (Garrett IV), William T. Anton.
Photo courtesy of Bowers and Ruddy.