It is a unit of account frequently used for digital gold currencies.
It is sometimes denoted by the symbol "gg", "AUG", or "GAU".
[1] A milligram of gold is sometimes referred to as a mil or mgg.
This allows gold holdings and transfers to take place in tiny fractions of a gram (equivalent to a few cents).
A possible source of confusion is that gold is often priced on the open market in the more traditional troy ounce (one troy ounce is exactly 31.1034768 grams, which is larger than the avoirdupois ounce generally in use in the United States and has a mass of 28.35 grams).