Sold these two already (for very nice prices I must say) but it would feel wrong not to share them.
The Dardanici mines were important sources of silver for Imperial Rome during the second century, notably during the time of Trajan. The mines are located in present-day Serbia.
To pay the workers of the mines, a special series of quadrans and semis were minted, presumably at Rome, featuring the personification of the province on the reverse.
Trajan AE semis
IMP CAES NERVA TRAIAN AVG, Laureate head right
DARDANICI, Dardanici standing, holding branch

Anonymous AE Quadrans, probably time of Trajan
ROMA, helmeted bust of Roma right
DARDANICI, Dardanici standing, holding branch

Both of these issues, along with the various other "mines" issues, are rare.