Thick cross is not exactly like on official coins. Maybe Vandals?
19324. Bronze AE 4, Fair, Heraclea? mint, 0.967g, 10.7mm, 404 - 406 A.D.; obverse D N ARCADIVS (or HONORIVS or THEODOSIVS) P F AVG, pearl diademed, draped and cuirassed bust right; reverse CONCOR-DIA AVGGG, cross, SMHB? in exergue; $99.00
This coin is a nummus of Valentinian III, mint of Rome. In obverse is readle the legend [DNPL]VALENTINIANVS[PFAVG]. In reverse the "placidian cross" and legend [SALVSRE]IPVB[LICE]. It is a coin very interesting because normal is Victory for Valentinian and Cross for Galla Placidia, bud exceptionally hay nummos with Victory fo Galla and Cross for Valentinian. Some numismatics considere this very scarce coin (Ric 2110) as mule. I know only 3 samples of this coin.