A rock is a solid naturally occurring hard, compact and tough substance which is made up of one or many minerals hence it is called as an aggregate of minerals. The three main types of rocks are sedimentarymetamorphic, and igneous. Our Earth’s outer solid layer, the lithosphere, is constituted by such aggregates only i.e. rock which typically forms recognizable and mappable volumes. The term ‘rock’ and ‘stone’ are virtually synonymous. The term stone is used for the small pieces of rocks of any shape and size. The physical and chemical makeup of rock depends essentially on the different attributes and mutual relationships of the constituent minerals, therefore, every rock has characteristics that reflect its process of formation; these are used to determine whether the rock is igneous, sedimentary or metamorphic; as the Rocks are commonly divided into three major classes according to the processes that resulted in their formation. The three main types of rocks are :

Types Of Rocks

(1) Igneous rocks:- which have solidified from the molten material called magma. These rocks are known as the Primary Rocks since these were the first formed rocks on the surface of the globe. Some of the typical examples of igneous rocks are- Granites, Basalts, Dolerites, Pegmatites etc. Read More

(2) Sedimentary rocks:- those consisting of fragments derived from pre-existing rocks or of materials precipitated from solutions. The most common sedimentary rocks are- Sandstone, Shales, Limestones, Coal-seams, etc. Read More…

(3) Metamorphic rocks:- which have been derived from either igneous or sedimentary rocks under conditions that caused changes in mineralogical composition, texture, and internal structure. The common metamorphic rocks are- Schists, Gneisses, Granulites, Slates, Marbles, etc. Read More…

These three types of rocks, in turn, are subdivided into numerous groups and types on the basis of various factors, the most important of which are chemical, mineralogical, and textural attributes.


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