This rock hails from Arizona. It reminds me of the rock I saw in New Mexico that was filled with petroglyphs. (See link http://www.nps.gov/petr/index.htm)The rock is pink in the middle and black around the outside -- like a good steak perfectly cooked actually. I would like to make my own petroglyphs on this rock...but won't. Measures approximately 5" across. A rather nice slab!