I keep learning about ancients and now I can identify this fella as Severus Alexander and the type of coin (sestertius) based on its size (about the same of a US 1/2 dollar.) However, I'm puzzled about the little stamp below the chin and the minting place. I found out that on the reverse there is an altar, but I couldn't find any info about the mint place and date. Any comments? Gratias!