Watch List notes:

4th century B.C. Disk-shaped Æ aes formatum (127 mm, ~1774 g). Mounded obverse, flat reverse. Haeberlin p. 4, pl. 2.7. Extremely rare. Green patina with heavy earthen deposits. As cast. 

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

Note that this is an especially heavy item (~2 lbs / 1 kg). Additional postage charges may (and will likely) apply.