L. Calpurnius Piso Frugi, Moneyers of the Roman Republic, Silver Denarius, struck at Rome 90 BC. Obverse: Laureate Bust of Apollo facing right, control mark “∩” to left. Reverse: Horseman galloping right holding palm frond and reins, control mark “XCII” above, “[L] PISO FRV[GI]” below. Sear-258; RSC-Calpurnia-11a. Struck slightly off centre, details Very Fine.
These particular control marks suggest L. Calpurnius rather than his son C. Calpurnius.