The original weight at minting was 26.73 grams. Of course a circulated coin will weigh slightly less.
Check the weight. A genuine U.S. Peace silver dollar should weigh 26.73 grams. If it's a replica, the weight will be off.
The standard weight of all Morgan and Peace dollars is 26.73 gm.
A 1922 silver dollar, also known as a Peace dollar, contains 0.7734 troy ounces of silver. Multiplying this weight by the current price of silver will give you an approximate value for the coin's silver content.
The link below has a picture of a peace dollar.
The is no 1921S Peace dollar; Peace dollars were not produced in San Francisco ("S" mintmark) in 1921. If your 1921 dollar coin is a Peace dollar, it was produced in Philadelphia and has no mintmark; if it has an "S" mintmark, it is a Morgan dollar produced in San Francisco).
A 1922 silver dollar, also known as the Peace dollar, weighs 26.73 grams. It is composed of 90% silver and 10% copper.
They stopped making the Peace dollar in 1935.
It's a Half Dollar NOT a dollar coin. The coin weighs 12.50 grams and contains .36169oz of pure silver.
An unworn Morgan dollar has a nominal weight of 26.7 grams. All Morgan dollars (as well as Peace dollars) were struck in an alloy of 90% silver and 10% copper, so they contain about 24.1 gm of pure silver, or about 0.77 troy ounces.
The image on the 1923 Peace Dollar is that of Lady Liberty.
The 1921 Peace dollar was minted to commemorate the end of World War I.
The last Peace dollar was issued in 1935 so it can't be a 1942 Peace dollar. Look at the coin again and post new question.