What is "felsic"

1912, from feldspar + silica + -ic.

a. (context mineralogy English) Enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. n. A rock with such properties.

In geology, felsic refers to igneous rocks that are relatively rich in elements that form feldspar and quartz. It is contrasted with mafic rocks, which are relatively richer in magnesium and iron. It refers to those rocks rich in silicate minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium.

They are usually light in color and have specific gravities less than 3. The most common felsic rock is granite. Common felsic minerals include quartz, muscovite, orthoclase, and the sodium-rich plagioclase feldspars. In terms of chemistry, felsic minerals and rocks are at the other end of the elemental spectrum from the mafic minerals and rocks.