The so-called transitional double eagle with 'In God We Trust' on the reverse. This reverse was adopted in 1866. These are believed to have been struck in 1865 although they may also have been restruck in the early 1870s.
The first appearance of this design was in the April 1870 auction by John Haseltine of coins from the Idler collection. Idler is famous today as one of the collector/dealers who had "connections" with the mint.
Over a dozen are believed known in copper as illustrated, several of which have been gilted. Some examples, including at least one of the 2 gold strikings, show a die crack in front of the one in the date as shown below.
Two examples of this design are known in gold J452/P524 Wilkison's, first offered in a June 1870 Mason and Company sale, the other in the Smithsonian.
An example in the Connecticut State Library ex D S. Wilson lot 1162, Mitchelson has been either silverplated or pickled. It is mentioned in Judd as being from the Robert Coulton Davis collection and was listed as J453A/P525 although this should not have a separate number. An earlier occurrence of this coin was probably lot 2438 in Woodward's 34th sale of 1881 where an example is described as probably a silverplated copper example. An example listed in aluminum J453B/P527 has not been seen since its original appearance in Woodward's 45th sale of the Dohrmann collection in 1882. The reverse is plated in the catalog and does not appear to be aluminum. It is probably a reappearance of the silverplated copper example as well.
Photos courtesy of Heritage.