Quartzite vs Plagioclase - What's the difference?
quartzite | plagioclase |
a metamorphic rock consisting of interlocking grains of quartz
(mineralogy) Any of a group of aluminum silicate feldspathic minerals ranging in their ratio of calcium to sodium.
*2004 , (Richard Fortey), The Earth , Folio Society 2011, p. 51:
*:These crystals are of one of the most abundant minerals in nature – feldspar; furthermore, they are of a particular kind of feldspar rich in the element calcium, termed plagioclase .