What Minerals Compose Granite

Granite is composed mainly of quartz and feldspar with minor amounts of mica amphiboles and other minerals.

What minerals compose granite. The essential minerals of granite are quartz k feldspar plagioclase of albite oligoclase composition. The common accessory minerals include biotite zircon apatite sphene with or without. Strictly speaking granite is an igneous rock with between 20 and 60 quartz by volume and at least 35 of the total feldspar consisting of alkali feldspar although commonly the term granite is used to refer to a wider range of coarse grained igneous rocks containing quartz and feldspar. Biotite may occur in granite of any type and is usually present though sometimes in very small amounts.

Chemical composition of the core corresponds to oligoclase and andesine an30 38 whereas more acidic oligoclase and andesine occur in the margin. Orthoclase quartz biotite muscovite and plagioclase which is twinned according to the albite law and oscillatory zoned. This mineral composition usually gives granite a red pink gray or white color with dark mineral grains visible throughout the rock. Granite typically contains 20 60 quartz 10 65 feldspar and.

Major minerals of granite.