Convert from firkin [butter, soap] to libra [Italy]

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 (libra [Italy])
The libra [Italy] is a traditional unit of weight. The libra was the Roman unit from which the English pound is descended; the symbol "lb" for the pound comes from this unit. The traditional Italian libbra was often of similar size, but a wide variety of libbras were used in Italian markets over the centuries. The word "libra" is sometimes used now for the kilogram, a much larger unit.