This section of the mountains is called Painted Wall.  Photo taken from the end of the southern road into Black Canyon of the Gunnison.  For details about the geology read below:

"Pink streamers of pegmatite animate the towering cliffs of the canyon at Painted Wall overlook. This granite-like igneous rock formed as hot magma forced its way into cracks. It cooled slowly, allowing large crystals to form. The pegmatite is loaded with shiny muscovite (mus'-ko-vite) mica and large crystals of a pinkish mineral called potassium feldspar.