Re: What are the parent rocks of gniess?

Well Danny that is a good question. As you may know a gneiss is defined as a 
high-grade metamorphic rock, always coarse grained and foliated, with 
marked compositional layering but with imperfect cleavage. (Skinner and 
Porter 1992).  The minerals composing the rock can usually tell you what the 
parent material is. So a gneiss with quartz, feldspar and micas should be 
an indication that the parent material was a granite.