Hand Sample
Thin Section Missing

Foid Monzogabbro

IUGS Definition ( QAPF Chart ) ( FAP Chart )

Foid Monzogabbro: "A collective term for basic alkaline plutonic rocks consisting of feldspathoids (10%-60% of the felsic minerals), calcic plagioclase with subordinate alkali feldspar and large amounts of mafic minerals."
Photos
Chemistry
Typical Minerals
  • feldspathoids
  • calcic plagioclase: labradorite or bytownite
  • orthoclase feldspar
  • clinopyroxene: augite or diopside
  • accessory minerals: olivine, orthopyroxene, hornblende, biotite