To make matters a little more interesting some FH Dollars also had a "Silver Plug" inserted in the center. They are rare and command a premium.
The alteration is right around where a "silver plug" would be located. This does not appear to have one but it did make my eyes do a double-take. I imagined one for several seconds.
Here is an interesting article on Early Dollars that provides some insight into why some of these coins may have a "silver plug" and that they may have been first discovered by "coin doctors", who were likely reluctant to come forward with the discovery due to their craft.
http://www.nationalsilverdollarroun....org/?p=1439Here are a few photos of the obverse and reverse comparing to a known "silver plug" coin.

