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Charnockite Rock

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Mother earth is filled with several different types of rocks. These rocks are formed due to years of suppression under the pressure applied by debris. Such rocks are called metamorphic rocks. They have been exposed to a large amount of pressure, change of season, and many earthly changes. This process is called metamorphosis and the process is responsible for contributing to the formation of several rocks found in nature. Charnockite rock is another type of rock that is a product of metamorphosis. There are many other rocks of a similar type. A few other examples are limestone, soapstone. Let us take a look at the physical and chemical properties of charnockite. 

Charnockite Rock Series

The charnockite rock series consists of several naturally occurring rocks which are a product of metamorphosis. Metamorphosis is the continual process of earthly debris being exposed to harsh weather conditions and pressure. This results in the formation of rocks, many of these rocks have a highly important application in various industries. Any orthopyroxene bearing quartz-feldspar formed at a high temperature and high pressure can be classified as a charnockite. Charnockite is a form of granofel. Granofel is any type of rock that has a granoblastic texture. An example of a granoblastic texture is given below

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The origin of charnockite is found to be in the deep crust between the tectonic plates deep into the earth’s layers of debris. The charnockite series rocks consist of rocks rich in felsic, quartz. Microcline, pyroxene, and olivine.

Properties of Charnockite Rock

There has been confusion about the class of charnockite rocks for a while now. Earlier, the charnockite series rocks were classified as igneous rocks. However, after some research, it was found that the charnockite series rocks are actually a variety of metamorphic rocks. This conclusion was made because in spite of rising temperature the protolith did not melt. Charnockites are found in several different colors. The color depends on the composition Of the rock. Each mineral has its own trademark color. The color of the charnockite series rocks can range from greasy green to aquamarine blue. Often, some rocks are brownish-green as well, this color in a charnockite rock indicates the High presence of titanium. The other commonly found colors include black, grey, orange, pink, and white.

The color also depends on the age of the rock and the amount of pressure the rock has been exposed to. The texture of the rock is generally described as coarse grainy and granoblastic. The rock directly found in nature is not soft to touch and has a pretty rough feel to it. However, when polished the rock’s texture softens. Generally, charnockite is anhydrous and essentially consists of orthopyroxene as its character-defining ferromagnetic mineral along with quartz and feldspar. 

The Naming of Charnockite Rocks

As iterated earlier, charnockite rocks were earlier thought of to be igneous rocks. It was believed that charnockite rocks are formed out of crystallized magma.  Hence, the charnockite rocks naming pattern follows the naming system of igneous rocks. Some charnockite rocks do contain traces of igneous rocks as well. Hence, we can say that charnockite rocks are a mixture of minerals and igneous rocks, and other debris found in nature. 

Fun Facts About the Charnockite Rock Series

The charnockite rocks are still being studied. Abundant deposits of charnockite rocks are found in the Nagercoil region of Tamil Nadu. However, not every property about the charnockite rock is known clearly.

The composition of charnockite is diverse, it is an agglomeration of several minerals and inorganic compounds. 

The minerals obtained in charnockite are Amphibole, Biotite, Feldspar, Hornblade, Micas, Muscovite or Illite, Olivine, Plagioclase, Pyroxene, Quartz. 

The chemical compounds found in charnockite are Aluminium Oxide, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Phosphorus Pentoxide, Silicon Dioxide, Titanium Dioxide. 

The rock is coarse and granular in nature. The rock has no luster whatsoever, i.e. they reflect minimal light and don't have a shiny appearance. The charnockite rock is highly non-porous, which means it does not allow water to seep through it. 

On the Mohs Hardness scale, charnockite rock scales between 6 and 7. Rocks in this range are moderately hard. 

What is the Difference Between Charnockite and Granite? 

Charnockite and granite are both types of rocks that have great utility in several industries. 

They are often confused to be the same, however, they are often confused to be the same. They have minute differences between them. Granite is an extremely hard, granular, crystalline igneous rock composed of minerals like quartz, mica, and feldspar and is mainly used as building stone. Charnockite is a type of granite that contains minerals such as orthopyroxene, quartz, and feldspar. Both of these have a similar utility and are often used in the construction industry. 

FAQ (Frequently Asked Questions)

1. What are the Uses of Charnockite? 

Ans: Charnockite has several utilities, it has many properties which make it highly suitable for construction. Charnockite is used in the construction of structures like roads, bridges, and buildings. They are also used in the field of pottery. They are used to make pots commonly found in the kitchen. Charnockite is also used as a gemstone to add to the home decor. It is also used to decorate the gardens. Charnockites are still being studied and it is believed that charnockites can also be used in the medical industry. However, this is possible only in the case of a few charnockites which have rare and exceptional properties.

2. Where is Charnockite Found?

Ans: Like any other rare metamorphic rock, the rocks of the charnockite series are also obtained in the earth's crust. They are mined out of the crust by digging deep. The first-ever deposit of charnockite was found in the state of Tamil Nadu in the Nagercoil district. These rocks are mainly found in the southern hemisphere. Deposits of rocks similar to the ones obtained in Tamil Nadu are found in  Norway, France, Sweden, Germany, Scotland, and North America. A commercial variety of charnockite rocks is found in Brazil. It is called “Green Ubatuba '' and is considered a pretty rare variety of rocks.