Watch List notes:

The Roman Empire
Caracalla, 198 – 217

Sestertius 213, Æ 30.30 g. M – AVREL ANTONINVS PIVS AVG BRIT Laureate head r. Rev. SECVRITATI PERPETVAE Securitas seated r., holding sceptre and resting head on r. hand; at her feet, lighted altar. In exergue, S C. C 573. BMC 250. RIC 512a.
A bold portrait struck on a very broad flan, lovely green patina and good very fine

Ex NAC 46, 2008, 1119 and Peus 400, 2010, 477. Illustrated in the book "Le preziose patine dei sesterzi di Roma imperial" by E. Biaggi, 1992, number 477. Illustrated on www.romancoins.info, section imagines imperatorum.
Short bearded portrait of Caracalla with the beginning, in my view, of his "sinister" expression.