Hand Sample Missing
Diorite Thin Section

Diorite

IUGS Definition ( QAPF Chart )( QAP Chart )

Diorite: "A plutonic rock consisting of intermediate plagioclase (An < 50), commonly with hornblende, and often with biotite or augite."
Typical Minerals
  • intermediate plagioclase: andesine or calcic oligoclase
  • hornblende
  • pyroxene: typically augite, but also orthopyroxene
  • biotite
  • quartz
  • olivine
  • magnetite
  • accessory minerals: apatite, sphene, ilmenite, zircon