There were no $1 silver certificates printed with that date. If you're referring to a $1 coin, please post a new question. Indicate how worn the coin is, and whether there is a small letter (D or S) under the eagle on the back side of the coin.
The intrinsic value is $14.16 with silver at $18.31 per ounce
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Assuming it's a more common Morgan dollar, about $13 for its silver content
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A average Mint State 1921 Morgan is $30.00-$40.00
The intrinsic value is $14.16 with silver at $18.31 per ounce
1922 silver dollar with closed eagle wings
A 1921 Half Dollar is 90% silver. It has a melt value of somewhere around $12. The related link below has more information.
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The '21 Morgan and '22 Peace are the most common years for those designs, usually selling for around $20-$30 each. The certificate value depends on series year, though anything dated 1935 or 1957 is typically only worth $2 or so. Then with the granules, value depends on weight and purity.
Assuming it's a more common Morgan dollar, about $13 for its silver content
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There is around .77 ounces in a 1921 US silver dollar.
There's a Peace dollar but not a war dollar. Please see the Related Question.
A average Mint State 1921 Morgan is $30.00-$40.00
1921 is by far the most common date for Morgan dollars -- current value is about $17.00
If the coin is a real Morgan or Peace dollar. The value is just for the silver, about $20.00.