What igneous rock has plagioclase feldspar biotite and amphibole?
Syenite: a plutonic rock composed mainly of alkali feldspar, with subordinate sodic plagioclase, biotite, pyroxene, and amphibole.
What is the difference between amphibole and biotite?
Instead of breaking in broad, single cleavage planes like the micas, the cleavage surface of an amphibole mineral tends to display a large number of small, offset planes that help give the mineral a splintery appearance. Biotite: Small black flakes with perfect cleavage in 1 direction (layers), reflects light.
What type of rock is amphibole?
Amphibolite is a coarse-grained metamorphic rock that is composed mainly of green, brown, or black amphibole minerals and plagioclase feldspar. The amphiboles are usually members of the hornblende group.
What igneous rock contains plagioclase biotite amphibole pyroxene and olivine?
Mafic rocks are dominated by plagioclase and pyroxene (even if you can’t see them with the naked eye) and smaller amounts of olivine. Intermediate rocks are roughly even mixtures of felsic minerals (mainly plagioclase) and mafic minerals (mainly hornblende, pyroxene, and/or biotite).
What would a rock that contains 30% quartz 20% alkali feldspar and 50% plagioclase feldspar be called?
According to the diagram, granite is defined as a coarse-grained igneous rock containing quartz, feldspar (both alkali and plagioclase feldspar), mica and sometimes amphibole.
Which type of igneous rock would you expect to contain 70% plagioclase feldspar?
Igneous Rock Charts
| Texture V | Color> | Medium to Dark Colored: Purple, Greenish |
|---|---|---|
| — | Minerals > | 55-70% plagioclase feldspar 15-40% biotite & amphibole |
| Composition | — | Intermediate |
| Fine = aphanitic | Extrusive volcanic | Andesite |
| Coarse = phaneritic | Intrusive plutonic | Diorite |
Is plagioclase mafic?
Mafic is used for silicate minerals, magmas, and rocks which are relatively high in the heavier elements. Common rock-forming mafic minerals include olivine, pyroxene, amphibole, biotite mica, and the plagioclase feldspars.
What is a biotite schist?
Mineral qualifiers are important when naming a schist. For example, a quartz-feldspar-biotite schist is a schist of uncertain protolith that contains biotite mica, feldspar, and quartz in order of apparent decreasing abundance.
Is amphibole a mineral or rock?
metamorphic rock
Amphibolite is a dark, heavy, metamorphic rock composed mostly of the mineral amphibole. Amphibolites have very little to no quartz. “Amphibole” refers not to a single mineral, but to a group of minerals.
What element is principally responsible for making olivine pyroxene amphibole and biotite dark?
silicate minerals. What element is principally responsible for making olivine, pyroxene, amphibole, and biotite dark? pyroxene and calcium-rich plagioclase feldspar.
Which rock contains moderate amounts of biotite amphibole and pyroxene?
Felsic, mafic, intermediate, or ultramafic: May be formed by fractional crystallization of olivine and pyroxene. Felsic, mafic, intermediate, or ultramafic: contains moderate amounts of biotite, amphibole, and pyroxene.