What Is The Percentage Of Plagioclase In A Typical Granite

Granite coarse or medium grained intrusive igneous rock that is rich in quartz and feldspar.

What is the percentage of plagioclase in a typical granite.

It is the most common plutonic rock of the earth s crust forming by the cooling of magma silicate melt at depth. A granite containing both muscovite and biotite micas is called a binary or two mica granite. True granite which has a quartz content between 20 and 60 percent and a greater concentration of alkali feldspar than plagioclase feldspar is only one of several granitoids. It depends on the granite but that is a reasonable value.

And the feldspar is both potassium feldspar and plagioclase. Learn more about the properties and uses of granite in this article. Applying this definition requires the mineral identification and quantification abilities of a competent geologist. The accepted classification scheme for felsic coarse grained magmatic rocks such as granite by its mineral content is via the qapf diagram where q stands for quartz a for alkali feldspar p for plagioclase feldspar and f for feldspathoid fig.

Two mica granites are typically high in potassium and low in plagioclase and are usually s type granites or a type granites. Granite is a plutonic rock in which quartz makes up between 10 and 50 percent of the felsic components and alkali feldspar accounts for 65 to 90 percent of the total feldspar content. A worldwide average of the chemical composition of granite by weight percent based on 2485 analyses.