Convert from scruple [troy] to arratel, artel [Arab]

Unit Definition (scruple [troy])
The scruple is a unit of weight in the traditional (troy) system used by English apothecaries, equal to 20 grains, 1/24 troy ounce or approximately 1.2960 gram.

Unit Definition (arratel, artel [Arab])
The arratel is a versions of a traditional Arab unit of weight; see rotl. The spelling "arratel" is used in Portugal as an alternate name for the libra.