Pitchstone Photos
Cochise College
Photos of Rocks        Igneous Rocks
Virtual Geology Museum       Hall of Rocks
Geology Home Page
Roger Weller, geology instructor                       

wellerr@cochise.edu    copyright 2011 

pitchstone, black-4
Pitchstone is dull, partially altered obsidian. 
 
 
pitchstone                                                                                                                                          1591
Photo is copyright free for non-commercial educational uses. 
Just credit photo to R.Weller/Cochise College