Unit Definition (pennyweight [troy]) The pennyweight is a unit of weight in the traditional troy system, equal to 24 grains or 1/20 troy ounce. One pennyweight is approximately 1.5552 gram.
Unit Definition (nanogram) The nanogram is a metric unit of mass equal to 10E-9 gram, or one millionth of a milligram.
Weight/Mass 
