In 2009 the U.S. Mint changed the reverse design of the Sacagawea Dollar. It also began calling them Native American Dollars since the reverse designs would now depict different Native American scenes. The coins would also have the date and mint mark on the edge of the coins.
The Special Strike 2009 Native American Dollars came in special Mint Sets for the year. Most of them were struck in superior quality ranging from about MS67 - MS68 condition. Nicer MS69 examples or higher were much more difficult to find.