Gn is the abbreviation of grain, sometimes written as "gr". It used to be used for weighing in the jewelry industry. It belongs to the British forces. The earliest 1gn is equivalent to 50 mg. This unit has been used in France before, but the French 1 15 mg.

Now it is uniformly stipulated that 1gn = 64.7438+0mg.

1g = 15.436gn