Taken from Lake Superior near Munising, MI.
They are called painted rocks because as rain water and drainage seeps through the porous rocks, the natural minerals and metals in the earth stain the rocks. The colors and bands “painted” on the rocks literally show the history and truth of the land.
We saw this particular formation while taking a local boat tour of the area. “Click here to visit boat company we used”: http://www.picturedrocks.com/