Andesite hand sample
Andesite thin section

Andesite

IUGS Definition ( QAPFv Chart )( QAPv Chart )

Andesite: An intermediate volcanic rock, commonly porphyritic, consisting of plagioclase, pyroxene, hornblende and/or biotite.”
Photos
Typical Minerals
  • plagioclase feldspar: labradorite, andesine
  • clinopyroxene: augite, pigeonite
  • hornblende and/or biotite
  • accessory minerals: ilmenite, magnetite