The Roman coinage was based on bronze coins until about 213-212 BC. The standard unit of weight was the libra (pound), which was divided into 12 unciae (ounces). A sextans was a sixth libra abd thus corresponded to two unciae, indicated on the obverse and reverse by two pellets.
The obverse of this early coin is interesting. It depicts the heroes of Rome's foundation legend, which had it that a she-wolf wet-nursed the twins Remus and Romulus. The parents of the twins were no other than Mars, the god of war, and the princess of Alba Longa, Rhea Silvia. As young men the twins founded the city of Rome. The reverse depicts an eagle with a flower in its beak and the inscription ROMA.