Tacitus Antoninianus, struck AD 276 at Serdica mint.
Obv: IMP C M CL TACITVS P AVG, Head right, radiate, with traces of drapery to front and rear of truncation.
Rev:
CONSERVAT MILIT / B // KA, Mars in military dress stg. r., holding
spear in l. hand, giving globe to Emperor stg. l., holding long sceptre
in l. hand.
3,66 g, 22 mm.
RIC temp 3898
traces of silvering
flan crack
extremely rare, only 2 specimens listed on RIC online