Porphyry Photos
Cochise College
Photos of Rocks       

Igneous Rocks
Geology Home Page
Roger Weller, geology instructor                       

wellerr@cochise.edu    copyright 2011    

granite porphyry-1
Mt. Whitney, California

Granite grains are the groundmass and the large feldspar crystals are the phenocrysts.

porphyry                                                                                                                              whitney8d

Photo is copyright free for non-commercial educational uses. 
Just credit photo to R.Weller/Cochise College.