Convert from quartern-loaf to obolus [Ancient Rome]

Unit Definition (quartern-loaf)
The quartern-loaf is a traditional English unit of weight for bread. A quartern-loaf is made from a quartern of flour. The finished loaf usually weighs somewhere between 4 and 5 pounds (very roughly 2 kilograms).

Unit Definition (obolus [Ancient Rome])
The obolus [Ancient Rome] is a historic unit of weight or mass. The obol is a very small weight that originated as the weight of a tiny Greek coin. In Rome, the obolus was equal to 1/48 Roman ounce (uncia) or about 0.57 gram.