Mesembria. 

Gordian III and Tranquillina AE, Mesembria, Thrace. 238–244 AD. 

AVT K M ANT GORDIANOC AVG CEB TPANKVLLINA, laureate, draped 
bust of Gordian III vis-à-vis draped bust of Tranquillina

MESAMBPIANWN, Hermes standing left, holding purse and caduceus, chlamys draped over left arm. 

Moushmov 4009. 

With permission of Roma Numismatics, May, 2010