The answer depends on the kind of salt that it refers to. A grain of table salt has a mass of a third to two-thirds milligrams. Large salt crystals, like those used in salt grinders (or for margaritas) have a mass of a milligram or more. The question is ambiguous: like "how long is a piece of string?"
What she says with a grain of salt
A grain of salt does not equal 1 milligram; rather, it is approximately 58 milligrams. This discrepancy arises from the historical use of the grain as a unit of measurement in the apothecaries' system, where 1 grain is defined as 1/7000th of a pound. In contrast, the metric system defines 1 milligram as 1/1000th of a gram. Therefore, a grain of salt is significantly larger than 1 milligram.
a grain of sugar
The mass of one grain of rice is 25 milligram or .025 grams. There are about 29,000 rice grains in approximately one pound of long-grain white rice.
Assuming you mean the obsolete mass unit rather than a grass seed. one grain is 64.799 milligrams.
milligrams
A grain of salt is typically measured in milligrams (mg) or micrograms (mcg). One grain of salt is equivalent to approximately 58 milligrams.
A precision balance or a microbalance can be used to accurately measure the mass of a grain of salt. These instruments are sensitive enough to measure very small amounts of mass with high precision.
And Take It with a Grain of Salt was created in 2002.
Depends how big the grain of salt is.
A grain can be a tiny piece of rock, yes. A grain can also be a grain of salt, meaning one 'pellet' of salt.
The expression "I took it with a grain of salt" meant "I didn't believe it".
There are approximately 58,000 nanograms in a single grain of salt.
What she says with a grain of salt
Large grain salt
With a Grain of Salt - 1913 was released on: USA: 14 March 1913
That's an impossible question to answer, as each one of the 1 million grains of sand will all be a different size and density, making each one of them weigh a different amount. Because of this, no 1 million grains of sand will weigh the same amount.