U.S. one dollar coins have been minted for more the 200 years at 5 different Mints. They have been struck in gold, silver, copper-nickel and brass..... so a date is very important for a value. Post...
If you mean all the one dollar coins made from 1971 to date, there just face value unless they are the collectors versions sold from the Mint, not the coins made for circulation.
First you need to check the back, above the "DO" in DOLLAR, for a mintmark. There may be a small "O", "S", or "CC" there. There may also be nothing there. In average circulated condition, with a "CC"...