Well I don't know much about coinage but ill try and help: This was in about 50-100 AD by the way: 1 pound 1 unit, about a labourers daily wage 5 pounds 4 sesterciis 100 pounds 100 sestercii or 25...
Roman currency of 2,000 years ago consisted of nearly pure silver coins, but less valuable metals were used in making coins during the 3rd and 4th century while the Roman Empire was declining.