Carat (mass) quarters" of 15 grains troy each. Likewise, the ounce troy was divisible into 24 "ounce carats" of 20 grains troy each; the ounce carat was divisible into four "ounce grains" of 5 grains troy each; and the ounce grain was divisible into four "ounce quarters" of grains troy each. The "solidus" was also a Roman weight unit. There is literary evidence that the weight of 72 coins of the type called "solidus" was exactly 1 Roman pound, and that the weight of 1 "solidus" was 24 "siliquae". The weight of a Roman pound is generally believed to have been 327.45
Grain (unit) weight) refers to those things measured by the lesser but quicker balances: the bismar or uncel, the Roman balance, and the steelyard. The original mercantile pound of 25 shillings or 15 (tower) ounces was displaced by variously the pound of the Hanseatic League (16 tower ounces) and by the pound of the then-important wool trade (16 ounces of 437 grains). A new pound of grains was inadvertently created as 16 troy ounces, referring to the new troy rather than the old troy. Eventually, the wool pound won out. The avoirdupois pound was defined in prototype, rated as to grains. In