Simple Lithology

gneiss

http://resource.geosciml.org/classifier/cgi/lithology/gneiss

definition Foliated metamorphic rock with bands or lenticles rich in granular minerals alternating with bands or lenticles rich in minerals with a flaky or elongate prismatic habit. Mylonitic foliation or well developed, continuous schistosity (greater than 50 percent of the rock consists of grains participate in a planar or linear fabric) precludes classification with this concept. more like this
narrower orthogneiss
broader gneiss
paragneiss
broader gneiss
source Neuendorf et al. 2005 more like this
type
Resource
Concept
broader foliated metamorphic rock
narrower gneiss
in scheme simplelithology
is primary topic of gneiss