Vandals
 

Geisarich, 428-477 Gunthamund, 484-496 Thrasamund, 496-523 Hilderich, 523-530 Gelimer, 530-534

Siliqua, Geisarich, 428-477, Lanz 123-1092

Siliqua, Gunthamund, 484-496, Lanz 123-1093

Siliqua, Thrasamund, 496-523, Lanz 123-1094

Siliqua, Hilderich, 523-530, Lanz 123-1095

Siliqua, Gelimer, 530-534, Lanz 123-1099-1102, below 1 Nummus, XII, XXI, XLII Nummi

"XLII" on Galba As, such countermarks are known to have been used by the Ostrogoths and Vandals to mark Sesterti as 83 Nummi (LXXXIII) and Dupondi as 42 Nummi (XLII). Interesting in that they prove coins being in circulation some 400 years or emore after their initial issue.
actually not a countermark, but cut into the coin
 

Below countermark "IIII" on a Constantine II coin, possible late Roman for 4 Nummi.

 

To the Byzantine Empire