Tranquillina AE20 of Nicaea, Bithynia. AD 241-244. 4.51 g. 

CAB TRANKYLLINA, draped bust right, wearing stephane.
N-I-K-AI between the masts of a legionary eagle between two standards, EWN below.

RecGen 723; BMC 130.

With permission of cngcoins.com, auction 257, Lot 233, June 2011.