Translation of legend abbreviations:

IOV(ΛIA)   MAMAIA   CEB(ACTH)   MHTE(P)   CE(BACTOV)   K(AI)  CTPA(TOΠEΔωN)

Julia Mamaea Augusta Mater (Mother) of Augustus (=Emperor) and the Camps

LIΓ

year 13

EGYPT, Alexandria.  Julia Mamaea

year 13, CE 233/4

tetradrachm, 24 mm, 14.36 gm

Obv:  IOVMAMAIACEBMHTECEKCTPA; Draped bust right, wearing stephane

Rev:  Serapis enthroned left, holding scepter, extending his right hand toward Cerberus seated at his feet; on throneback, Nike standing right, holding wreath and palm frond; L IΓ (date) to left, palm frond to right

Ref:   Emmett 3226.13 (R4);  Köln 2540; Dattari (Savio) 4517; K&G 64.119