Convert from firkin [butter, soap] to qian [China]

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 (qian [China])
The qian is a traditional Chinese weight unit. In modern China the qian is equal to 0.1 liang, or exactly 5 grams (0.1764 ounce).