Origin of plagioclase
Examples from the Web for plagioclase
A dark, compact rock, having a mottled appearance due to grains of plagioclase, and a green color in section.The Long Labrador Trail|Dillon Wallace
The former consist mainly of plagioclase, leucite and augite, while the latter contain olivine in addition.
The felted or hyalopilitic texture is the most common, and plagioclase is the principal groundmass constituent.Mount Rainier|Various
On the right hand side part of a plagioclase crystal with inclosures similar to that in the preceding figure.Etna|G. F. Rodwell
Minettes contain biotite and orthoclase; kersantites, biotite and plagioclase.
"triclinic feldspar," 1868, from German, coined 1847 by German mineralogist Johann Friedrich August Breithaupt (1791-1873) from plagio- + Greek klasis "fracture," from stem of klan "to break" (see clastic). Related: Plagioclastic.