Sicily.   Messana.   The Mamertinoi.     AE Onkia, c. 220-200 BC.   Obv.    Laureate head of Apollo left; behind, symbol.        Rev.   MAMERTINΩN. Omphalos.     CNS I 28; HGC 2 884 var. (no symbol); Buceti 27.     3.60 g.   13.00 mm.      RR.  Rare issue. Olive-green patina.    VF.