Unit Definition (picogram) The picogram is a metric unit of mass equal to 10E-12 gram or one millionth of a microgram.
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.
Weight/Mass 
