Paint Mines Interpretive Park
In the wilderness areas of El Paso county in Colorado is a colourful site set in a landscape of hoodoos that provided Amerindians with clay for pigments (used for warpaint and ceramics) since 7,000 BCE. Now protected by the National Parks Service, the area was shaped by erosion by the endless winds and occasional flash floods into fantastic shapes. The fragile formations are of many hues, ranging from creamy white, to orange, purple, gray, rust, and chocolate brown.
The area was uplifted along with the rest of the American west by subduction off the Pacific coast, pushing formations upwards and compressing them as exotic terranes collided and agglutinated themselves to the continental mass. The colours are caused by iron within the clays, and reflect the passage of waters through the rocks, oxidising and reacting with them to produce the beautiful hues. Archaeologists have excavated plenty of pottery coloured by clays from this location in the area.
Image credit: Dave Soldano
More stunning photos: http://www.electricreflections.com/paint-mines-interpretive-park.html