Exactly the value of the copper in the coin. No more. The current price of copper is about $3.50 pound. So your coin just has sentimental value.
Most coins are not silver, unless your coin has an "S" mintmark, it is copper and nickel and only worth $1.
There were no official commemorative cents struck for the Bicentennial. If you have a coin with extra markings on it, it's been altered by a private company and is worth 1¢ If you have an otherwise ordinary looking 1976 cent, it's also only worth 1¢
None of the bicentennial coins regardless of denomination released into circulation are worth more than face value.
Assuming it has a copper-colored edge, it's a copper-nickel Bicentennial coin worth 50 cents. Please see the related question for details
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The bicentennial dollar coin is still worth one dollar.
There were no bicentennial designs for cents, nickels, or dimes. If your coin is from 1976 it's worth exactly 10 cents.
Canada has not celebrated a bicentennial. The 1967 coin is the Centennial penny. It's worth face value, .01 cent.
The bicentennial dollar coin is still worth one dollar.
The 1976-S Bicentennial 3-piece coin set is worth in proof condition $15-$20. In uncirculated condition, its value is: $17-$20.
The US Mint did not issue a bicentennial coin in 1972. Pleas examine the coin and submit a new question giving more details concerning it.
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