From your description the coin is a common Susan B. Anthony dollar (1979-1981 & 1999) that is in circulation today. It's just a dollar coin, spend it.
One dollar.
A 1979 US dollar coin is still worth one dollar.
It's still worth one dollar.
A US half dollar with a date of 1979 is a Kennedy half dollar not a liberty half dollar. The coin has no silver and is only face value.
Round?
It's still only a dollar
The US $1 dollar coin dated 1979 has no silver in it, they are still in circulation if this coin is from pocket change spend it.
They use the US Dollar.
With a date of 1979 the coin has no silver in it. 1969 was the last 40% silver circulating US half dollar. The coin is worth 50 cents.
In 1979, the dollar coin issued by the US was the Susan B. Anthony, which has no silver content and no real collector's value, so is a "spender".
A 1979 US Liberty Dollar is also known as a Susan B. Anthony Dollar. It has a value, depending upon its condition, of $1.30 to $140, and is not among the most widely collected coins.
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