7mm and weighs .6g
the obverse has what looks like glue, so I am soaking it in acetone
I just saw a similar example attributed to the Vandals--
Lot 110. VANDALS. Pseudo-Imperial coinage in the name of Justinian I. 548-565. Æ Nummus (8mm, 0.72 g, 6h). Carthage mint. Bust right / Christogram. BMC Vandals 28; cf. MEC 1, 33; SB 283; DOC I 311. Brown patina, rough obverse. VF.