Please post a new question with the coin's date. Carson City minted silver dollars for about 20 years.
About $27.
42cents
About $150.
"DO" isn't a mint mark. The mint mark on a silver dollar for that year is on the reverse (tails) side, just above the letters "do" in the word "dollar."
One Dollar
about $25 depending on condition and mint mark
By the mint mark on the reverse of the coin, but silver dollar coins with no mint mark are made in Philadelphia
They are still found in circulation, have no silver and are only face value
If the coin has any wear the value is for the silver, about $8.50
No mint marking
No mint mark means it was minted in Philadelphia.
The mint mark on any Morgan dollar is on the reverse above the letters DO in dollar.