Convert from fotmal [lead] to teragram

Unit Definition (fotmal [lead])
The fotmal is a traditional English unit of weight for lead. In medieval England the fotmal was equal to 70 "mercantile" pounds, which is equivalent to 72 avoirdupois pounds.

Unit Definition (teragram)
The teragram is a metric unit of mass equal to 1012 grams or 1 megatonne (one million metric tons). This unit is frequently used in atmospheric science and other scientific contexts where large masses are considered.