grain (gr) [1] (We use this definition 7000 grains in
an avoirdupois
pound. 1 grain = 64.798 91 milligrams) |
a traditional unit of weight. The grain, equal to 1/480 troy ounce (see
also pound [2]), or exactly 64.798 91 milligrams, was the legal foundation
of traditional English weight systems, with various pounds being defined
as a specified number of grains: 5760 grains in a troy pound and 7000
grains in an avoirdupois pound, for example. In the version
of the troy system used by jewelers, there are 24 grains in a pennyweight
and 20 pennyweight in an ounce. In the version used by apothecaries, there
are 20 grains in a scruple, 3 scruples in a dram, and 8 drams in an ounce.
Originally the grain was defined in England as the weight of a barleycorn.
This made the English grain larger the corresponding grain units of France
and other nations of the Continent, because those units were based on the
weight of the smaller wheat grain. |
grain (gr) [2] |
a unit of weight formerly used by jewelers in measuring diamonds and
other precious stones. The jeweler's grain is exactly 1/4 carat. Now that
the carat has been standardized at 200 milligrams, the jeweler's grain
is exactly 50 milligrams, or approximately 0.7716 troy grain. This unit
is widely used for measuring pearls, so it is sometimes called the pearl
grain. |
grain (gr) [3] |
a traditional French unit of weight equal to 53.115 milligrams. |