On Frank Holt's interpretation, Diodotus introduced a new coinage while still satrap, which consisted of a large number of silver tetradrachms and, later, a small number of gold staters. These coins have the head of a male figure on the obverse, presumably Diodotus himself, shown wearing the diadem—a band of cloth wrapped around the head, with two strips hanging down the back, which had been the standard symbol of Hellenistic kingship since the time of Alexander the Great. The image seems to gradually age over time, suggesting that it was intended as a realistic portrait of Diodotus. The reverse of these coins abandoned the Seleucid god Apollo in favour of a depiction of Zeus preparing to throw his thunderbolt. The choice of Zeus may have been intended as a reference to Diodotus himself whose name meant 'Gift of Zeus' in Greek. Alternatively, it may look back to early coinage struck by Seleucus I, from which the reverse image is taken. The legend on the reverse of these coins still reads ('Of King Antiochus'). The coinage thus clearly proclaimed Diodotus' authority, but retained some ambiguity about the extent of his independence from the Seleucids. An alternative interpretation advanced by Jens Jakobsson is that this is the coinage of a separate king Antiochus Nicator, whom he interprets as a younger son of grandson of Diodotus, and whose rule he would place around the 220s BC.
On Frank Holt's interpretation, Diodotus introduced a new coinage while still satrap, which consisted of a large number of silver tetradrachms and, later, a small number of gold staters. These coins have the head of a male figure on the obverse, presumably Diodotus himself, shown wearing the diadem—a band of cloth wrapped around the head, with two strips hanging dow.n the back, which had been the standard symbol of Hellenistic kingship since the time of Alexander the Great The image seems to gradually age over time, suggesting that it was intended as a realistic portrait of Diodotus. The reverse of these coins abandoned the Seleucid god Apollo in favour of a depiction of Zeus preparing to throw his thunderbolt. The choice of Zeus may have been intended as a reference to Diodotus himself whose name meant 'Gift of Zeus' in Greek. Alternatively, it may look back to early coinage struck by Seleucus I, from which the reverse image is taken. The legend on the reverse of these coins still reads ('Of King Antiochus'). The coinage thus clearly proclaimed Diodotus' authority, but retained some ambiguity about the extent of his independence from the Seleucids. An alternative interpretation advanced by Jens Jakobsson is that this is the coinage of a separate king Antiochus Nicator, whom he interprets as a younger son of grandson of Diodotus, and whose rule he would place around the 220s BC.