Cents, nickels, dimes, quarters, and half dollars were struck at both Philadelphia (no mint mark back then) and Denver (D mint mark)
All US Proof sets of 1964 and before have silver coins in them, the current value of a 1958 set is $43.00 issue price was $2.10
A 1955 US Mint set contained 22 coins. It had 2 coins from each Mint that produced coins for circulation. All US Mint sets from 1947 through 1958 are double sets.
The US Mint did not issue any silver coins of any kind in 1980. If you have silver coins dated 1980, they are not US coins.
1794 was the first Federal issue silver coin, a Dollar.
As best I can tell the US did not issue any $20 bills dated 1958. That makes it worth about 20 years in federal prison.
US Mint statistics report 87,376,722 regular issue coins and 2,018 mint "Proof" coins. Unless uncirculated these coins are very common.
It's common and circulated coins are only valued for the silver, about $12.00
1794 was the first Federal issue silver coin, a Dollar.
The U.S. does not issue "Tallar" coins.
The U.S. Mint did not issue a 1979 Silver Proof set. None of the coins contain any silver.
The average is 3 to 5 cents each
The U.S. didn't issue any $1 coins in 1958, and no circulating gold coins have been minted since 1933. Please post a new question with more details including a description of the coin and its country of origin. Use the Discussion area if the question box isn't large enough.