This experimental piece was supposedly struck in an alloy of 90% silver and 10% nickel but no examples are known.
Examples are known as follows: To see images of most of these, click
with at least 10 known including examples in the American Numismatic Society, Connecticut State Library, Durham Museum and Princeton University. Earlier editions of Judd listed this as silver-nickel but all examples tested by Dave Cassel were more or less standard coin nickel (75% copper, 25% nickel) with no silver found at all. With the 8th edition, this number is now listed as nickel.
with at least 8 known including examples in the Connecticut State Library and Durham Museum.
Photo courtesy of PCGS and is the former Simpson coin.