Convert from rotl, rotel, rottle, ratel [Arab] to tael, tahil [Japan]

Unit Definition (rotl, rotel, rottle, ratel [Arab])
The rotl, rotel, rottle, ratel is a traditional Arab unit of weight corresponding to the Roman libra, the French livre, and the English pound. There was considerable variation in the unit from time to time and from place to place, but usually the rotl was about 0.9-1.15 pound (450-530 grams). However, in some areas of the Near East, such as Syria and Palestine, larger rotls of 5.5 to 6 pounds (2.5-2.8 kilograms) were used. This unit has many spellings in European languages.

Unit Definition (tael, tahil [Japan])
The tael, tahil [Japan] is a traditional unit of weight used throughout eastern Asia. During the colonial period, the tael was more or less standardized throughout the region at 4/3 ounce avoirdupois (1/16 catty, 1/12 pound, or about 37.8 grams). In Japan, however, the tael was identified with a slightly smaller traditional unit and is considered equal to 1.323 ounces (37.51 grams). The tael is usually considered equal to the Chinese liang.