Hi guys, I have this 2006 P South Dakota Quarter and see that there are incused areas on both the obverse and reverse of this coin. On the obverse the incused area's are located above Washington's head starting at the "F" in OF and continuing to the "R" in America. Below the "Y" in Liberty and continuing up underneath Washington's Neck and also one spot in the middle of Washington's neck. Lastly, near the "T" in Trust. On the Reverse, the incused areas are below the bird/above the faces, and at the bottom on the quarter on the left side above the wreath along the bottom of faces. (See photo's). Can someone explain what this is?
