This seems like an irregular issue:
MAXIMINUS II DAIA as AUGUSTUS (310-313)
AE20mm 4.05g copper silvered follis, minted at Alexandria, fifth group, sixth coinage, cca. late 312-early 313.
IMP C GAL VAL MAXIMINVS P F AVG; laureate head right
GENIO - AVGVSTI·; Genius standing left, modius on head, naked but for chlamys over left shoulder, right hand holding head of Serapis, left hand holding cornucopia; N over palm branch in left field, Z in right field
ALE in exergue
cf. RIC VI Alexandria 157b (unlisted officina Z)
This issue is lighter and of a smaller size than usual for the type and the dot between AVGVSTI and ALE looks like part of the mintmark rather than the legend.