15 BC. and later, Augustus, imitative Dupondius, irregular Balkan? mint, cf. RIC 381.

Augustus, imitative Dupondius, 7,71 g., 26 mm, irregular Balkan mint?, 15 BC. and later.
Obv.: AVGVSTVS / TRIBVNI[C] / POTES[T] , in three lines in oak-wreath.
Rev.: [C N P]ISO CN [F III V]IR A A A F [F] , aroung big S C , two countermarks: CA
BMCRE p. 29, no. 135 note ; CBN 446-7 .
regular issues: cf. RIC 381 ; cf. CBN 439 ; cf. C 378 .

(this coin was in a lot of other coins from Macedon and Viminacium)

the weight-peaks for regular dupondii of this issue are 11.50 - 13.50 g.
a regular specimen (28 mm, 13.24 g.) of this issue cf.: http://www.coinarchives.com/a/
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