Foidolite

Foidolite ( /ˈfɔɪdəlaɪt/) is a rare coarse-grained intrusive igneous rock in which more than 60% (by volume) of light-coloured minerals are feldspathoids.[1] Crystals of alkali feldspar, plagioclase, biotite, amphibole, pyroxene, and/or olivine may be present within the rock. The volcanic equivalents are termed foidite and phonolitic or tephritic foidites.

Foidolite (sodalitolite variety) from Namibia
Thin section of foidolite under polarizing microscope. In the foreground there is a large yellow sodium pyroxene grain surrounded by fine grains.

Some foidolites are a potential source of aluminium.

See also

References
  1. Le Maitre, R.W. (editor) (2002). Igneous Rocks — A Classification and Glossary of Terms (2nd edition). Cambridge: Cambridge University Press. pp. 4, 22, 24, 82. ISBN 0-521-66215-X.CS1 maint: extra text: authors list (link)
  • Foidolite (at University of Manitoba) - Retrieved 2009-05-15


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.