Convert from marc [France] to rotl, rotel, rottle, ratel [Arab]

Unit Definition (marc [France])
The marc is a traditional units of weight in various countries of Western Europe. In each country the unit equals 1/2 the unit corresponding to the English pound. Thus the French marc equals 1/2 livre, 8 onces or about 244.75 grams; the Spanish marco equals 1/2 libra or about 230 grams; the German mark equals 1/2 pfund or about 280.5 grams; and the English mark equals 8 ounces or 226.8 grams. The English unit was used almost entirely for measuring precious metals.

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.