phonolite
Sign in to savethumb|Demonstration of sound produced when phonolite is struck, Cerro de la Campana (Hermosillo, Sonora, Mexico) thumb|Lithophone made of Phonolite in Schellerhau botanic garden (Germany)
Key facts
- Rock.name
- Phonolite
- Rock.alternative_name
- Clinkstone
- Rock.type
- Extrusive igneous
- Rock.type_link
- extrusive rock
- Rock.image
- Aegirine-phonolite2-2005.jpg
- Rock.alt
- A greenish-grey rock with fine dark linear features embedded
- Rock.caption
- Dark, prismatic phenocrysts of aegirine in phonolite sample
- Rock.composition
- nepheline, sodalite, hauyne, leucite, analcite, sanidine, anorthoclase
- Rock.composition_secondary
- biotite, amphibole, pyroxene, olivine
via Wikipedia infobox
Article
11 sectionsContents
- Formation
- Mineralogy and petrology
- Occurrence
- Examples
- Africa
- Europe
- North America
- Other
- Economic importance
- References
- External links
thumb|Demonstration of sound produced when phonolite is struck, Cerro de la Campana (Hermosillo, Sonora, Mexico) thumb|Lithophone made of Phonolite in Schellerhau botanic garden (Germany)
Phonolite is an uncommon shallow intrusive or extrusive rock, of intermediate chemical composition between felsic and mafic, with texture ranging from aphanitic (fine-grained) to porphyritic (mixed fine- and coarse-grained). Phonolite is a variation of the igneous rock trachyte that contains nepheline or leucite rather than quartz. It has an unusually high (12% or more) Na2O + K2O content, defining its position in the TAS classification of igneous rocks. Its coarse grained (phaneritic) intrusive equivalent is nepheline syenite. Phonolite is typically fine grained and compact. The name phonolite comes from the Ancient Greek meaning "sounding stone" due to the metallic sound it produces if an unfractured plate is hit; hence, the English name clinkstone is given as a synonym.