Under Gordian III, Soli-Pompeiopolis in Cilicia made coins inscribed with ΑϚ, interpreted as coins of 6 assaria. However, the earlier coins for Alexander and Maximinus are sometimes inscribed ΒϚ, whose interpretation has long remained a puzzle. The same letters ΑϚ and ΒϚ also occur on some fairly small coins of Sidon during the first century AD.
Clearly ΑϚ and ΒϚ cannot then be value marks. What then are they? All are also dated by a year, according to a relevant era for each city. So it seems possible that ΑϚ and ΒϚ might qualify the year date in some way, and they refer to the first and second period of six months of the year. Such ‘semesters’ are attested at a number of Greek cities.
The implications for our understanding of Roman provincial denominations will be explored.