Δ in circular punch

Uncertain mint, likely of Balkan origin. Septimius Severus. Æ 28 (4 Assaria?). A.D. 193-211. Obv: (...)CE(...). Laureate, draped and cuirassed bust right; countermark behind head. Rev: Inscription largely obliterated, N (?) in exurge. Artemis (?) running right. Axis: 225°. Weight: 13.09 g. CM: Δ in circular punch. Howgego 781, 783, 784 (?). Note: Δ countermarks have recently been found on many coins of the region, indicating that the coins in question are valued at 4 assaria. Collection Automan.