This one was misidentified as a coin of Faustina II at auction, but I knew it was Plautilla. It's from an obscure Phrygian city that issued coins only intermittently. Plautilla, AD 202-205. Roman provincial Æ 20.0 mm, 4.15 g, 7 h. Phrygia, Otrus, AD 202-205. Obv: ΦOVΛ ΠΛ-AVTIΛΛAC, bare-headed and draped bust, right. Rev: OTP-O-HNΩN, Demeter standing left, holding grain ears and long torch. Refs: BMC 25.344,7; Von Aulock Phrygiens, 802-8; cf. SNG Cop 633.