Ancient Roman Æ Sestertius of Emperor Severus Alexander

This is an ancient Roman Æ orichalcum Sestertius, of Emperor Severus Alexander, minted at Rome in 231 AD 

Obverse: IMP SEV ALEXANDER AVG, laureate head right

Reverse: ANNONA AVGVSTI, S-C across fields, Annona standing left, holding grain-ears over modius with grain-ears set on ground and anchor.

CULTURE: ROMAN

DENOMINATION: Sestertius

MATERIAL: Æ orichalcum

DATE: 222 - 235 AD (minted at Rome in 231 AD)

SIZE: 28mm diameter

WEIGHT: 16.38 grams

ATTRIBUTION:  RIC 548; Cohen 35; Sear 7962.

PROVENANCE: Formerly in a private collection. London