What is the value of a bar dollar?

Answer 1

You could be referring to a variety of the 1890 CC Morgan dollar which has a "bar" connecting the wreath to the eagle's tail feathers. This was caused by a damaged die.

Another possibility is that you're thinking of BARR dollars, which are $1 bills dated 1963B and signed by Treasury Secretary Joseph Barr. Barr only served for one month so many people erroneously think that very few bills were printed and any you find are valuable. However, so-called "Barr notes" were actually printed for nearly a year and they're quite common - in fact, nearly a half-billion were put into circulation.

Please determine which item you're interested in and post a new, separate question.