RARE Tacitus Double Antoninianus  275-276 AD

Denomination : AR Antoninianus.

Mint : Antioch mint, 4th officina. 3rd emission, early-mid AD 276

Date : AD 276

Obverse : IMP C M CL TACITVS AVG, radiate, draped, and cuirassed bust right.

Reverse : CLEMENTIA TE MP, Aurelian standing right, holding eagle-tipped scepter and receiving globe from Jupiter standing left, holding scpeter; Δ//XI. RIC V 211 (Antoninianus); BN p. 436; Venèra

An interesting and peculiar mark, the ‘XI’ on the coinage of Tacitus appears to have signified a higher silver content than the usual issue of Antoniniani. The study by Esty, Equall, and Smith (“The Alloy of the ‘XI’ Coins of Tacitus,” in NC 1993) corroborates the earlier study by Callu, Brenot, and Barrandon (“Analyses de Séries Atypiques,” in QT 8) showing that, though the consistency of the latters findings were not as universal, the series with this notation does exhibit a far higher silver content than the common ‘XXI’ marked coinage and represented an issue tariffed at a higher rate.