Convert from firkin [butter, soap] to tonelada [Portugal]

Unit Definition (firkin [butter, soap])
The firkin [butter, soap] is a traditional unit of weight for butter and soap, equal to 4 stone or 56 pounds (about 25.40 kilograms).

Unit Definition (tonelada [Portugal])
The tonelada [Portugal] is a traditional weight unit of Portugal corresponding to the English and metric ton. The Portuguese tonelada, however, equals 1728 Portuguese libras or arratels; this is about 1748.6 pounds or 793.15 kilograms.