Foidolite

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.

Foidolite (pronunciation: /ˈfɔɪdəlt/) is a rare coarse-grained intrusive igneous rock with a feldspathoid mineral content greater than 60%. 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.

Some foidolites are a potential source of aluminium.

See also

External links


This article is issued from Wikipedia - version of the 8/15/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.