Mineralogy Of Granites

 Granite is known to be the Earth's most famous invasive stone. Granite has an appearance of a mottled pink, continental crust, Decorative rock colored in white, gray, and black. It has large to Average-grained Feldspar, its three principal minerals, are Quartz, mica, and muscovite, Or dark biotites, or either of them. Of the minerals here Feldspars prevails the most, quartz accounts for Over 10 percent of the rock. The Alkali Feldspars are usually yellow, resulting in pink Sometimes seen in the pink granite as a stylish rock.

Mineral Formation in Granites

The Granite rocks are formed from the hydrothermal fluids, during the last stages of magmatic differentiation in which the hydrothermal fluids are enriched with felsic minerals and solutions, as illustrated in the Bowen’s reaction series diagram we can see that, granites are usually formed at low temperatures that enable the minerals to crystals. For more information on the formation of granites, you can refer to the formation process on the basic petrology page.

There four most common types of minerals that can be found in granite include:


One of the most common minerals in the crust of the earth is, Quartz which has two forms;    Macrocrystalline and cryptocrystalline(Microscopic crystals).   Macrocrystalline quartz is commonly Colorless and clear, like rock crystals or white crystals.   Even transparent, for instance, milky quartz,    pink and transparent rose quartz;    purplish amethyst, and Transparent black or brown smoky quartz.

Potassium Feldspar

Among the feldspar solid-solution series, potassium feldspar commonly known as orthoclase is an essential rock-forming mineral.    It's one of the key minerals in granites that displays a pink crystal,    giving granite its standard quality.    Orthoclase occurs in varieties of colors that include colorless, cream,    pale yellow, and brownish-red.   It has prismatic well-formed with short crystals that are often twinned.    An example of orthoclase with the schiller effect is a Moonstone.


Muscovite is part of the mica group, which frequently appears as colorless, silvery-white, brown, pale green, light gray, and rose red. Muscovite has tabular crystals that have a pseudo-hexagonal design. Consist of granular aggregates with thin flats sheets. It is also known as sericite, often occurs in gneisses, schists, granites, and pegmatite.


Biotite an end member of the solid solution series was once known as a mineral.   It is composed of annite, iron, phlogopite, and magnesium. It is part of the mica series that has wide tabular thin sheets and prismatic hexagonal crystals that can be observed in thin section. Biotite displays a black color when iron-rich and brown, pale yellow and bronze when magnesium-rich.


The economical significance of granite is mainly industrial due to its hardness and resistance to weathering and as a decorative ornament. It can be reshaped and resized to fit a particular purpose or crushed to form aggregates that can be used in construction.

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