After the "as" had been issued as a cast coin for about seventy years, and its weight had been reduced in several stages, a "as" was introduced (meaning that it weighed one-sixth of a pound). At about the same time a silver coin, the denarius, was also introduced. Earlier Roman silver coins had been struck on the Greek weight standards that facilitated their use in southern Italy and across the Adriatic, but all Roman coins were now on a Roman weight standard. The denarius, or 'tenner', was at first tariffed at ten "asses", but in about 140 BC it was retariffed at sixteen "asses". This is said to have been a result of financing the Punic Wars.