Phonolite Photos          

Cochise College                                                           
Photos of Rocks
Igneous Rocks
Geology Home Page
Roger Weller, geology instructor               


last edited:  11/15/16    number of photos:  2
Phonolite is a fine-grained, extrusive igneous rock
whose primary mineral content is a sodium feldspar
(albite) or sanidine. 
If the magma had cooled slower and formed larger grains,
it would have been a nepheline syenite.

phonolite:  1  2


Photos are copyright free for non-commercial educational uses. 
Just credit photos to R.Weller/Cochise College.
copyright 2016-R.Weller