Watch List notes:

Anonymous. 4th century B.C. Aes Formatum (114 mm, 940 g). Very Rare. Mounded obverse / Flat reverse. Haeberlin p. 4, pl. 2.7. As made, with earthen adhesions. 

Called aes formatum by Haeberlin, this very rare bronze currency was a precursor to the issues of aes grave but later than aes rude.