Kiglapait Syenite Hand Sample
Kiglapait Syenite Thin Section

Syenite

IUGS Definition ( QAPF Chart ) ( QAP Chart )

Syenite: "A plutonic rock consisting mainly of alkali feldspar with subordinate sodic plagioclase, biotite, pyroxene, amphibole and occasional fayalite. Minor quartz or nepheline may also be present."
Photos
Typical Minerals
  • alkali feldspar: perthitic orthoclase or microcline
  • plagioclase feldspar, typically as pethitic components
  • biotite
  • clinopyroxene
  • amphibole
  • quartz (less than 5%)
  • accessory minerals: sphene, apatite, zircon, opaque oxides, olivine