Convert Ton (Assay) (US) (AT (US)) to Grain (gr) instantly.
About these units
Ton (Assay) (US) (AT (US))
The US assay ton is a specialized unit used in mining and metallurgy for evaluating ore grades. It is defined as 29.166⅔ grams, a very small mass chosen to simplify calculations relating assay results to tons of ore. The idea is that if an assay ton of sample yields 1 milligram of precious metal, then one actual ton of ore contains 1 ounce of that metal. This scaling makes laboratory results directly translatable to mining yields. While obsolete in modern industrial practice, where metric units dominate, the assay ton remains important in historical mining records and for researchers studying early industrial metallurgy.
Grain (gr)
The grain, defined as exactly 64.79891 milligrams, is one of the oldest units of mass still in limited use today. Derived from the weight of average cereal grains such as barley or wheat, it became a universal tiny unit used across Europe for coins, medicine, and gunpowder. The grain persists in firearms and ammunition manufacturing because bullet weights are still listed in grains (e.g., a "150-grain bullet"). Reloaders and ballistic engineers rely on the grain as a fine unit suitable for measuring powder charges and projectile masses. It is also used in traditional gold and silver transactions, linking it to the troy system. The grain's longevity highlights how ancient agrarian measures can remain embedded in modern technological practices.